19 Eia Racks

Alibaba.com

Overview

Product sourcing insights & recommendations

www.datainsightsmarket.com
en.wikipedia.org
29 来源

The market for 19-inch EIA racks is evolving rapidly, driven by the expansion of hyperscale data centers, 5G network infrastructure, and high-density AI computing StatsmarketresearchVerifiedmarketreports. The global market was valued at USD 1.25 billion in 2024 and is projected to reach USD 2.1 billion by 2033, growing at a CAGR of 6.6% Verifiedmarketreports.

Key Market & Product Trends

  • Hyperscale & AI Demand: The proliferation of hyperscale data centers is shifting demand toward larger, high-density racks. While 42U remains the enterprise standard, there is a clear trend toward 45U to 48U configurations to maximize space in AI-driven data centers PayapressDatainsightsmarket.
  • Edge Computing Growth: The rise of localized data processing is fueling the demand for smaller form factors, specifically 6U, 9U, and 12U wall-mount cabinets for telecommunications and decentralized IT setups VerifiedmarketreportsDatainsightsmarket.
  • Advanced Cooling Systems: As power density increases, innovations are moving toward liquid cooling and liquid-hybrid cooling racks to manage heat more effectively than traditional air cooling PayapressMarketintelo.
  • Modular Mounting Innovations: A significant mechanical shift is the move from threaded holes to square holes with floating cage nuts, allowing for replaceable threads and support for multiple screw types (M6, 10-32, 12-24) within the same unit Payapress.

Standardization & Technical Insights

The EIA-310 standard (specifically EIA-310-D) remains the bedrock of global interoperability, ensuring that hardware from major brands like Intel, Dell, and HPE fits seamlessly into racks produced by different manufacturers RacksolutionsPayapress.

  • Rack Unit (U): Standardized at 1.75 inches (44.45 mm), allowing for precise space planning WikipediaRacksolutions.
  • Mounting Width: While the front panel is 19 inches, the usable internal width between rails is typically 17.75 inches PayapressRacksolutions.

The following files provide detailed sourcing data for 19-inch EIA racks, including pricing and supplier information for 42U data center cabinets, high-density liquid-cooled racks, and wall-mount network enclosures.

Based on these market trends, you can continue with:

19 Inch Eia Server Rack 42u Data Center

Products · 3 lists

OEM Network Server Rack 42U Metal Network Cabinets Data Center Server Rack Cabinet

OEM Network Server Rack 42U Metal Network Cabinets Data Center Server Rack Cabinet

$127.644.9(898)
MOQ: 1 piece
EIA standard42U
Langfang Gometal Network Equipment Co., Ltd.Langfang Gometal Network Equipment Co., Ltd.verified🇨🇳CN5 yrs
6U 9U 12U 19 Inch Data Center Server Rack 42U Floor Standing Glass Door Network Cabinet

6U 9U 12U 19 Inch Data Center Server Rack 42U Floor Standing Glass Door Network Cabinet

$2304.2(996)
MOQ: 2 pieces
EIA standard42U≤2h response time
Chengdu Bolein Technology Co., Ltd.Chengdu Bolein Technology Co., Ltd.🇨🇳CN8 yrs
OEM ODM 19 Inch 42U Network Cabinet 800x2000x800mm Floor Standing Server Rack Data Center 42U Network Cabinet

OEM ODM 19 Inch 42U Network Cabinet 800x2000x800mm Floor Standing Server Rack Data Center 42U Network Cabinet

$147.25-1595.0(188)
MOQ: 10 pieces
EIA standard42U7% reorder rate≤3h response time
Langfang Zhongcheng Dingli Furniture Co., Ltd.Langfang Zhongcheng Dingli Furniture Co., Ltd.verified🇨🇳CN6 yrs
36U 37U 42U Server Rack Network Cabinet 19 Inch Standard Floor Standing Data Center Enclosure for Switch Room

36U 37U 42U Server Rack Network Cabinet 19 Inch Standard Floor Standing Data Center Enclosure for Switch Room

$1655.0(853)
MOQ: 2 pieces
EIA standard42U50% reorder rate900+ views from America≤6h response time
Ningbo GLGW Nova Materials Technology Co., Ltd.Ningbo GLGW Nova Materials Technology Co., Ltd.verified🇨🇳CN1 yr
WebiTelecomms 19 Inch ANSI/EIA Standard Floor Standing Server Rack 42U 600x600mm SPCC Glass Door Network Cabinet Data Center

WebiTelecomms 19 Inch ANSI/EIA Standard Floor Standing Server Rack 42U 600x600mm SPCC Glass Door Network Cabinet Data Center

$165-2154.0(959)
MOQ: 5 units
EIA standard42U500+ store reviews≤4h response time
Ningbo Hi-Tech Zone Webit Telecommunication Equipments Co., Ltd.Ningbo Hi-Tech Zone Webit Telecommunication Equipments Co., Ltd.verified🇨🇳CN16 yrs
Manufacturer OEM Data Center Server Rack IT 19 Inch Ddf 18u 22u 32u 42u Unit Indoor Network Switch Cabinet

Manufacturer OEM Data Center Server Rack IT 19 Inch Ddf 18u 22u 32u 42u Unit Indoor Network Switch Cabinet

$62-675.0(433)
MOQ: 2 pieces
EIA standard42U
Xianghe Zhongyuebohua Hardware Co., Ltd.Xianghe Zhongyuebohua Hardware Co., Ltd.verified🇨🇳CN4 yrs
36U 37U 42U 19 Inch EIA Standard Floor Standing Server Rack Network Cabinet Vented Glass Mesh Doors Heavy Duty SPCC Steel for

36U 37U 42U 19 Inch EIA Standard Floor Standing Server Rack Network Cabinet Vented Glass Mesh Doors Heavy Duty SPCC Steel for

$161.704.0(918)
MOQ: 2 pieces
EIA standard42U≤1h response time
CRYSTAL DRINK COMPANY LIMITEDCRYSTAL DRINK COMPANY LIMITED🇹🇭TH1 yr
42u Data Center Network Cabinet 19 Inch Rack Mount Standard Server Outdoor Black OEM/ODM

42u Data Center Network Cabinet 19 Inch Rack Mount Standard Server Outdoor Black OEM/ODM

$331.80-363.404.5(976)
MOQ: 1 set
EIA standard42U≤3h response time
Shenzhen Reybow Networking Technology Co., Ltd.Shenzhen Reybow Networking Technology Co., Ltd.🇨🇳CN1 yr
Network Data Center Server Rack Cabinet19'' Inch 37U/42U 800*800mm  Server Rack Data Center

Network Data Center Server Rack Cabinet19'' Inch 37U/42U 800*800mm Server Rack Data Center

$1404.9(946)
MOQ: 20 sets
EIA standard42U200+ store reviews29% reorder rate≤2h response time
Shenzhen Idealink Network Technology Co., Ltd.Shenzhen Idealink Network Technology Co., Ltd.🇨🇳CN11 yrs
19-Inch ANS EIA RS-310-D IEC297-2 Standard 42U Perforated Server Racks with Heavy Duty Castors with Braked Data Center Cabinets

19-Inch ANS EIA RS-310-D IEC297-2 Standard 42U Perforated Server Racks with Heavy Duty Castors with Braked Data Center Cabinets

$130-1814.3(971)
MOQ: 10 pieces
EIA standard42U
Ningbo Latitude International Trade Co., Ltd.Ningbo Latitude International Trade Co., Ltd.verified🇨🇳CN9 yrs
42U 1200mm Deep GPU Rack Data Center Network Cabinet 19 Inch Rack Mount Standard Server AI Data Center Infrastructure

42U 1200mm Deep GPU Rack Data Center Network Cabinet 19 Inch Rack Mount Standard Server AI Data Center Infrastructure

$50-1505.0(481)
MOQ: 1 piece
EIA standard42U
Ningbo Turn-Link Network Communication Equipment Co., Ltd.Ningbo Turn-Link Network Communication Equipment Co., Ltd.verified🇨🇳CN15 yrs
High Quality Wall Mount Data Center Ddf Network Server Cabinet Server Rack Outdoor 6U Metal Network Cabinets

High Quality Wall Mount Data Center Ddf Network Server Cabinet Server Rack Outdoor 6U Metal Network Cabinets

$104.9(70)
MOQ: 2 pieces
EIA standard42U
Hebei Huateng Yizhou Electrical Equipment Co., Ltd.Hebei Huateng Yizhou Electrical Equipment Co., Ltd.verified🇨🇳CN5 yrs
GETEKnet OEM ODM 19" Indoor Data Center Rack 6u 9u 12u 18u 22u 32u 42u 47U Wall Mount 19 Inch Telecom Network Server Cabinet

GETEKnet OEM ODM 19" Indoor Data Center Rack 6u 9u 12u 18u 22u 32u 42u 47U Wall Mount 19 Inch Telecom Network Server Cabinet

$29-3885.0(822)
MOQ: 10 pieces
EIA standard42U
Ningbo Geteknet Telecom Equipment Co., Ltd.Ningbo Geteknet Telecom Equipment Co., Ltd.verified🇨🇳CN8 yrs
Standing 42U Colocation Server Rack

Standing 42U Colocation Server Rack

$200-5803.9(386)
MOQ: 1 set
EIA standard42U≤5h response time
Zhejiang Safewell Precision Sheet-Metal Mfg., Ltd.Zhejiang Safewell Precision Sheet-Metal Mfg., Ltd.🇨🇳CN14 yrs
19inch 42U 45U 48U  Network Cabinet Data Center Server Rack Cabinet

19inch 42U 45U 48U Network Cabinet Data Center Server Rack Cabinet

$340-3904.6(672)
MOQ: 1 piece
EIA standard42U50+ store reviews≤3h response time
Ningbo Aze Imp & Exp Co., Ltd.Ningbo Aze Imp & Exp Co., Ltd.🇨🇳CN7 yrs
Starlink 19 Inch 42U Network and Server Rack Cabinet in Data Center

Starlink 19 Inch 42U Network and Server Rack Cabinet in Data Center

$80-2204.1(258)
MOQ: 5 pieces
EIA standard42U
Ningbo Starlink Communication Equipment Co., Ltd.Ningbo Starlink Communication Equipment Co., Ltd.🇨🇳CN2 yrs
Gcabling Smart Micro Modular Data Center Containment Cooling System 19 Inch Integrated Network Cabinet Server Rack with 42u

Gcabling Smart Micro Modular Data Center Containment Cooling System 19 Inch Integrated Network Cabinet Server Rack with 42u

$7,9004.7(752)
MOQ: 1 piece
EIA standard42U1100+ store reviews9% reorder rate≤4h response time
Ningbo Getek Communiactions Equipment Co., Ltd.Ningbo Getek Communiactions Equipment Co., Ltd.🇨🇳CN6 yrs
15U/18U/22U/27U/32U/37U/42U/47U Network Cabinet Server Rack 19 Inch Network Rack Net Door Stock

15U/18U/22U/27U/32U/37U/42U/47U Network Cabinet Server Rack 19 Inch Network Rack Net Door Stock

$55-2204.9(167)
MOQ: 2 pieces
EIA standard42U200+ store reviews17% reorder rate≤1h response time
Guangzhou Brothers Lin Electronics Co., Ltd.Guangzhou Brothers Lin Electronics Co., Ltd.verified🇨🇳CN9 yrs
Professional Manufacturer IP20 Indoor Network Cabinet 2000mm Height 42U 19 Inch Floor Standing Steel Server Rack

Professional Manufacturer IP20 Indoor Network Cabinet 2000mm Height 42U 19 Inch Floor Standing Steel Server Rack

$229.47-289.714.8(494)
MOQ: 10 pieces
EIA standard42U2500+ store reviews≤1h response time
Guangzhou Weipo Industry & Trade Co., Ltd.Guangzhou Weipo Industry & Trade Co., Ltd.🇨🇳CN6 yrs
19 Inch 42u Rack Server Cabinet for Data Center Spcc Cold Rolled Steel Heavy-duty High Loading Capacity Rack Network Enclosure

19 Inch 42u Rack Server Cabinet for Data Center Spcc Cold Rolled Steel Heavy-duty High Loading Capacity Rack Network Enclosure

$179.99-199.993.9(816)
MOQ: 10 pieces
EIA standard42U≤5h response time
Ningbo Gam Global Trading Co., Ltd.Ningbo Gam Global Trading Co., Ltd.🇨🇳CN12 yrs
Data Center 19 Inch Network Cabinet with Mesh Door 42U Server Rack IP20 Protection SPCC Steel CE Certified

Data Center 19 Inch Network Cabinet with Mesh Door 42U Server Rack IP20 Protection SPCC Steel CE Certified

$50-3004.5(459)
MOQ: 10 pieces
EIA standard42U
Ningbo Shangyang Technology Co., Ltd.Ningbo Shangyang Technology Co., Ltd.verified🇨🇳CN2 yrs
22U*600*600 19" International Standard Vented Server Cabinet Network Rack Size Data Center 18U,22U,32U,37U,42U for Toten

22U*600*600 19" International Standard Vented Server Cabinet Network Rack Size Data Center 18U,22U,32U,37U,42U for Toten

$754.6(112)
MOQ: 10 pieces
EIA standard42U100+ store reviews62% reorder rate≤3h response time
Guangzhou Laixuan Electronic Co., Ltd.Guangzhou Laixuan Electronic Co., Ltd.🇨🇳CN6 yrs
Popular Manufacturers Low-cost 19-inch Standard 42U Rack Cabinet Network Outdoor Network Cabinet Server Rack

Popular Manufacturers Low-cost 19-inch Standard 42U Rack Cabinet Network Outdoor Network Cabinet Server Rack

$1985.0(672)
MOQ: 10 pieces
EIA standard42U
Cixi City Jiasheng Network Equipment Co., Ltd.Cixi City Jiasheng Network Equipment Co., Ltd.verified🇨🇳CN21 yrs
19-Inch Data Center Network Cabinet 42U High 600x1000 Server Rack

19-Inch Data Center Network Cabinet 42U High 600x1000 Server Rack

$199-2094.0(248)
MOQ: 1 piece
EIA standard42U≤1h response time
Beijing Hanhai Tech Co., Ltd.Beijing Hanhai Tech Co., Ltd.🇨🇳CN5 yrs
Factory OEM 42U 19 Inch Data Center Server Rack Floor Standing Network Enclosure SPCC Steel IP66 Protection IT Telecom Equipment

Factory OEM 42U 19 Inch Data Center Server Rack Floor Standing Network Enclosure SPCC Steel IP66 Protection IT Telecom Equipment

$102.40-2005.0(698)
MOQ: 1 unit
EIA standard42U20% reorder rate≤1h response time
Ningbo Sail Tool Technology Co., Ltd.Ningbo Sail Tool Technology Co., Ltd.🇨🇳CN2 yrs
18U 22U 24U32U 38U 42U 47U Data Center Network Cabinet 19 Inch 42 U Rack Mount Standard Server Outdoor Server Rack

18U 22U 24U32U 38U 42U 47U Data Center Network Cabinet 19 Inch 42 U Rack Mount Standard Server Outdoor Server Rack

$16.99-20.994.3(834)
MOQ: 1 piece
EIA standard42U
Wuhan Snnju Precision Manufacturing Co., Ltd.Wuhan Snnju Precision Manufacturing Co., Ltd.verified🇨🇳CN1 yr
High Quality Server Computer Cabinet 19 Inch Network Cabinet Rack 42u Server Network Cabinet Fireproof Server Rack

High Quality Server Computer Cabinet 19 Inch Network Cabinet Rack 42u Server Network Cabinet Fireproof Server Rack

$62-744.3(805)
MOQ: 1 piece
EIA standard42U≤1h response time
Beijing Guojian Anping Electric Power Construction Development Co., Ltd.Beijing Guojian Anping Electric Power Construction Development Co., Ltd.🇨🇳CN2 yrs
19 Inch 42U Fireproof Server Rack Thick Manufacture Network Cabinet for Data Centers Fiber Optic Equipment

19 Inch 42U Fireproof Server Rack Thick Manufacture Network Cabinet for Data Centers Fiber Optic Equipment

$115.20-1694.9(829)
MOQ: 1 unit
EIA standard42U400+ store reviews28% reorder rate≤3h response time
Shenzhen Aeon Telecom Technology Co., Ltd.Shenzhen Aeon Telecom Technology Co., Ltd.🇨🇳CN6 yrs
42U Server Cabinet Data Center Server Rack Network Cabinet for Sale

42U Server Cabinet Data Center Server Rack Network Cabinet for Sale

$135-2055.0(562)
MOQ: 1 piece
42U
Shenzhen Jingzhi Network Equipment Co., Ltd.Shenzhen Jingzhi Network Equipment Co., Ltd.verified🇨🇳CN4 yrs
19inch Standard Server Rack 42U Customized Network Cabinet Data Center IT Equipment Accessories

19inch Standard Server Rack 42U Customized Network Cabinet Data Center IT Equipment Accessories

$350-3895.0(534)
MOQ: 10 sets
42U
NEW SUNPLN TECHNOLOGY INDUSTRIAL CO., LTD.NEW SUNPLN TECHNOLOGY INDUSTRIAL CO., LTD.verified🇨🇳CN4 yrs

Sources & References

29 sources cited · Verified industry data & reports

Understanding Growth Challenges in 19-inch Racks Market 2026-2034

www.datainsightsmarket.com

The telecommunications sector also represents a significant growth avenue, with continuous investments in 5G network expansion and infrastructure upgrades necessitating reliable rack solutions for network equipment. Furthermore, the increasing adoption of high-quality audio and visual equipment in professional music production and live event setups, coupled with a rising trend of sophisticated home entertainment systems, is contributing to market expansion. Our analysis delves into market concentration, key trends, regional dominance, product specifics, driving forces, challenges, and emerging opportunities, painting a comprehensive picture of this dynamic sector. The 19-inch racks market exhibits a moderate level of concentration, with key players dominating specific application segments. The unprecedented growth in cloud computing and the Internet of Things (IoT) has created a colossal demand for robust and scalable data storage and processing infrastructure, directly benefiting the 19-inch racks market. The market is witnessing a significant trend towards high-density rack solutions, enabling users to house more equipment within a smaller footprint. Manufacturers are responding by developing innovative rack designs that optimize airflow, facilitate efficient cooling, and support higher power delivery capabilities, anticipating a market value in the hundreds of billions by the end of the forecast period. Furthermore, the increasing adoption of edge computing is a substantial trend reshaping the market.

19-inch rack - Wikipedia

en.wikipedia.org

The EIA standard was revised again in 1992 to comply with the 1988 public law 100-418, setting the standard U as 15.875 mm (0.625 in) + 15.875 mm (0.625 in) + 12.7 mm (0.500 in), making each U 44.45 millimetres (1.75 in). The 19-inch rack format has remained constant while the technology that is mounted within it has changed considerably and the set of fields to which racks are applied has greatly expanded. The formal standards for a 19-inch (482.6 mm) rack are available from the following: Electronic Industries Alliance EIA-310-D, Cabinets, Racks, Panels, and Associated Equipment, dated September 1992. ↑ "Rack specifications - Define EIA-310". Portable rack cases using a rotary-molded polyethylene outer shell are a lower-cost alternative to the more durable ATA-approved case. These cases are marketed to musicians and entertainers for equipment not subject to frequent transportation and rough handling. A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is 19 inches (482.6 mm) wide. The 19-inch dimension includes the edges or ears that protrude from each side of the equipment, allowing the module to be fastened to the rack frame with screws or bolts.

19-inch Racks Market, Global Outlook and Forecast 2026-2032

www.statsmarketresearch.com

19inch Racks Market, 19inch Racks Market Size, 19inch Racks Market Revenue, 19inch Racks Market Segmentation, 19inch Racks Market CAGR value These racks are designed to securely hold and house different devices and components, such as servers, networking equipment, audiovisual gear, and other electronic devices, in a standardized form factor. The standard 19-inch width, defined by the Electronics Industries Alliance (EIA), ensures interoperability across a vast ecosystem of manufacturers and products, which is a key factor driving their widespread adoption. 1 Introduction to Research & Analysis Reports 1.1 19-inch Racks Market Definition 1.2 Market Segments 1.2.1 Segment by Type 1.2.2 Segment by Application 1.3 Global 19-inch Racks Market Overview 1.4 Features & Benefits of This Report 1.5 Methodology & Sources of Information 1.5.1 Research Methodology 1.5.2 Research Process 1.5.3 Base Year 1.5.4 Report Assumptions & Caveats 2 Global 19-inch Racks Overall Market Size 2.1 Global 19-inch Racks Market Size: 2024 VS 2032 2.2 Global 19-inch Racks Market Size, Prospects & Forecasts: 2020-2032 2.3 Global 19-inch Racks Sales: 2020-2032 3 Company Landscap This growth directly translates into a higher demand for server racks, as these standardized enclosures are the foundational building blocks for housing servers, switches, and storage arrays. The trend towards hyperscale data centers, which can contain hundreds of thousands of servers, further underscores the critical and continuous need for reliable, scalable rack solutions that optimize space, power distribution, and cooling efficiency.

What is a 19 inch rack? - RackSolutions

www.racksolutions.com

This is the same group of people who standardized the term “rack unit” and other words used in the space today. EIA claims that the reasons for standardization is to “increase market share, boost quality levels and elevate customer satisfaction.” Though, it should be noted that EIA has no authority over the industry, other than their highly reputable recommendation. A server rack is a standardized, vertical frame that is designed to securely hold and organize multiple IT devices such as servers, routers, and switches. The standard was created by the Electronic Industries Alliance or EIA. To meet the 19 inch EIA standard, a server chassis width will need to be less than 17.75 inches. Any larger than this and you will not be able to insert the server through the front. Additionally, your rails or shelves needs threaded holes 18.31 inches apart. The front panel width, which refers to the actual panel of your server, is the only dimension that needs to be 19 inches. This measurement runs from essentially the outer edge of one square hole on the rack to the outside of a perpendicular square hole. If you have a 19 inch rack and are worried about your server not fitting it, chances are you’ll be fine. Even though the 19 inch EIA standard isn’t a requirement, major brands like Intel, Dell, HPE and IBM adhere to the standards on their servers.

19-Inch Rack Market Research Report 2033

marketintelo.com

The regulatory landscape for the 19-inch rack market is evolving in response to growing concerns around data security, equipment safety, and environmental sustainability. Industry standards such as EIA-310, IEC 60297, and RoHS compliance are critical considerations for manufacturers, ensuring interoperability, safety, and environmental responsibility. Furthermore, the proliferation of hyperscale data centers and the growing adoption of 5G networks are expected to fuel sustained demand for advanced rack solutions in the Asia Pacific region. Emerging markets in Latin America, the Middle East, and Africa are witnessing a noticeable shift in market dynamics, driven by regulatory reforms, demographic trends, and economic diversification efforts. Key trends include modular and customizable rack designs, integration with advanced cooling and power management systems, energy efficiency, enhanced security features, and the adoption of intelligent racks with sensors and remote monitoring capabilities. Chapter 1 Executive SummaryChapter 2 Assumptions and Acronyms Used Chapter 3 Research Methodology Chapter 4 19-Inch Rack Market Overview 4.1 Introduction 4.1.1 Market Taxonomy 4.1.2 Market Definition 4.1.3 Macro-Economic Factors Impacting the Market Growth 4.2 19-Inch Rack Market Dynamics 4.2.1 Market Drivers 4.2.2 Market Restraints 4.2.3 Market Opportunity 4.3 19-Inch Rack Market - Supply Chain Analysis 4.3.1 List of Key Suppliers 4.3.2 List of Key Distributors 4.3.3 List of Key Consumers 4.4 Key Forces Shaping the 19-Inch Rack Market 4.4.1 Bargaining Power of Suppliers 4.4.2 Bargaining Power

What Are EIA Standards? And Where Do They Come From?

aj-racks.com

Posted by A & J Manufacturing on June 28, 2022 4:44 pm | Comments Off on What are EIA Standards? And Where Do They Come From? A 19-inch rack is a standardized frame or enclosure for mounting electronic equipment modules. Common uses for these racks / enclosures include datacom, telecommunication, audiovisual production equipment, scientific equipment, and networking hardware. The weird thing: almost nothing on a 19″ rack measures 19 inches. The term comes from the width of the front panel of the boxes that are installed in the rack. Other common rack hole-to-hole spacing includes 23″ (566.7 mm) and 24″ racks (592.1 mm). EIA stands for the Electronic Industries Alliance. The height of the different panels will vary, but in all cases to be a whole multiple of 1.75 inches.” · By 1934, it was an established standard with holes tapped for 12-24 screws with alternating spacings of 1.25″ and 0.5″. The standard was again revised in 1992 to comply with the 1988 public law 100-418, setting the standard U as 1.75″ (44.45 mm). The 19-inch format has more or less remained constant since despite the fact that the technology mounted within has changed considerably. A 19″ rack format with 1.75″ or 1U was established as a standard by AT&T around 1922 in order to reduce the space required for repeater and termination equipment in a telephone company’s central office. Their engineering department created a family of modular panels “designed to mount on vertical supports spaced 19.5 inches between centers.