Middle Atlantic MRK-3731
Rack with Rear Door (37 Space, 31" Deep)

OUR PART #  MRK-3731


Features & Specifications:

  • Fully welded construction, open sides
  • UL Listed in the US and Canada
  • 2,500 lb. weight capacity
  • Seismic certified (UBC 1997 & CBC 1998 Zone 4; IBC 2000, IBC 2003, ASCE 7 - 02, NFPA 5000 Seismic Use Group III) for protecting 1000 lbs. of essential equipment when used in conjunction with our MRK-Z4 brackets
  • Slim 22" OD width
  • Available in 4 depths: 26.5", 31.5", 36" & NEW! 42 "
  • 2 pairs of wider rackrail provide more interior room
  • Laser-cut 1/8" thick internal steel braces for strength
  • 14-gauge steel tops & bottoms, 16-gauge seamless steel sides
  • Grounding and bonding stud installed in base
  • Configurable open top accepts a number of top options
  • Keylocked solid rear door standard
  • Finished in a durable black textured powder coat
Middle Atlantic PDLT-815RV-RN Rack Light with Power

Middle Atlantic PDLT-815RV-RN Rack Light with Power

PDLT-815RV-RN Rack Light with 15 Amp Power Distribution and Surge Suppression Status NotificationMiddle Atlantic Products PDLT-815RV-RN Specifications: Multifunctional PDLT Series Rack Light and PowerDistribution Unit designed to improve ...
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In Stock
Middle Atlantic BR-2 Brush Grommet Panel (2 Space, 3.5")

Middle Atlantic BR-2 Brush Grommet Panel (2 Space, 3.5")

The brush grommet panels provide a clean, organized cable entry method when used in conjunction with any work surface. Features a built-in cable management tray. Available in 1 and NEW 2 space versions. 2 space brush grommet panel fits in ...
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In Stock
Middle Atlantic HPQ 100-Piece Phillips Screws with Washers

Middle Atlantic HPQ 100-Piece Phillips Screws with Washers

Cable friendly HPQ series screws are 3/8" long with 10-32 threads and feature a rounded end to allow wires to be dressed inside front rackrail without chafing. Featuring an attractive Phillips truss head, finished in black oxide.
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In Stock
Middle Atlantic HTX 50 Pack Torx Star-Post screws and washers

Middle Atlantic HTX 50 Pack Torx Star-Post screws and washers

These 10-32 by 3/4" security screws feature a star post drive. All screws have a self-guiding pilot point, black oxide finish and come with factory installed nylon washers in lots of 50. Star post drive bits available.
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In Stock
Middle Atlantic HPS 25-Pack of 10-32 x 3/4" Phillips Head Screws with Nylon Washer

Middle Atlantic HPS 25-Pack of 10-32 x 3/4" Phillips Head Screws with Nylon Washer

Middle Atlantic's HP series rackscrews are 3/4" long with 10-32 threads and feature an attractive Phillips truss-head for a clean modern appearance. All screws have a self-guiding pilot point, include factory installed nylon washers for ...
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In Stock
Middle Atlantic WS4-M31-24 WS Series Multi-Bay Laminate Writing Shelf Laminated 1" Thick 4 Bay Writing Shelf with Durable T-mold Edge and Cable Grommets

Middle Atlantic WS4-M31-24 WS Series Multi-Bay Laminate Writing Shelf Laminated 1" Thick 4 Bay Writing Shelf with Durable T-mold Edge and Cable Grommets

The WS Series writing shelves from Middle Atlantic provide a secure work surface for their WRK, MRK, VRK and VMRK Series enclosures when used in multi-bay applications. This model, the WS4-M31-24 is intended to be used as a 4 Bay Writing ...
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Usually ships in 6-10 business days.
Middle Atlantic MW4QFT-FC Integrated Fan Rack Top for WRK, MRK, DRK, VRK, VMRK Racks, 200 CFM with four 4.5" fans

Middle Atlantic MW4QFT-FC Integrated Fan Rack Top for WRK, MRK, DRK, VRK, VMRK Racks, 200 CFM with four 4.5" fans

Integrated fan tops save time and money, and simplify ordering Includes proportional speed thermostatic fan control to ensure that fans only run when needed, extending fan life, reducing noise and maintenance requirements Ships ...
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Usually ships in 4 business days.
Middle Atlantic SPN37-312 Pair of Side Panels/Black 37-space 31-32" deep

Middle Atlantic SPN37-312 Pair of Side Panels/Black 37-space 31-32" deep

Our SPN series side panels fit all WRK, MRK, VMRK and VRK, series enclosures. These side panels feature stylish beveled corners to match the aesthetics of the enclosure, easily lift on and off, and include an internal locking kit. Black ...
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Usually ships in 6-10 business days.
Middle Atlantic WS2-M31-18  2-Bay 18" Deep Writing Shelf for 31" Deep MRK and VRK Racks

Middle Atlantic WS2-M31-18 2-Bay 18" Deep Writing Shelf for 31" Deep MRK and VRK Racks

Designed to provide an ergonomic work space, the Middle Atlantic WS2-M31-18 writing shelf is designed for Middle Atlantic's 31" deep MRK and VRK Series enclosures. Offered in a two-bay size to span multiple ganged ...
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Usually ships in 6-10 business days.
Middle Atlantic MW10FT-FC Integrated Rack Fan Top for MRK, WRK, DRK, VRK, VMRK Racks, One 10" fan 550 CFM

Middle Atlantic MW10FT-FC Integrated Rack Fan Top for MRK, WRK, DRK, VRK, VMRK Racks, One 10" fan 550 CFM

NOTE:  A 4-fan top is pictured, this is a single fan top. Integrated fan tops save time and money, and simplify ordering Includes proportional speed thermostatic fan control to ensure that fans only run when needed, extending fan ...
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Usually ships in 6-10 business days.
Middle Atlantic MW10FT-550CFM Integrated Fan Top (with One 10" Fan)

Middle Atlantic MW10FT-550CFM Integrated Fan Top (with One 10" Fan)

Top options accept 10" fans for active thermal management.  All tops include a removable two-space service plate that allows removal of top without disrupting cable bundles. Features/Specifications: Includes one 10" fan ...
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Usually ships in 6-10 business days.
Middle Atlantic VFD-37 Vented Front Door 37 Space

Middle Atlantic VFD-37 Vented Front Door 37 Space

This Vented Front Door VFD-37 (Black) is the perfect addition to an existing rack, increasing the level of security and protection for your valuable equipment. The rack's beveled corners offer a stylistically modern appearance while the ...
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Usually ships in 6-10 business days.
Middle Atlantic FD-37 37Sp Solid Front Door

Middle Atlantic FD-37 37Sp Solid Front Door

Offered in lightly smoked plexiglass, fully vented, vented plexi, NEW large perforated vented and solid configurations. Beveled corners provide a stylistically modern appearance, while hinging either left or right. Large perf door has 68% ...
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Usually ships in 6-10 business days.
Middle Atlantic CBS-MRK-31 Castor Kit MRK Rack/31"Deep

Middle Atlantic CBS-MRK-31 Castor Kit MRK Rack/31"Deep

With a 1300 lb. capacity, our commercial grade caster bases are equipped with heavy duty non-locking 3" swivel wheels and are UL listed in the US and Canada. NEW fine floor caster bases now available with a 700 lb. weight capacity. Each ...
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Usually ships in 6-10 business days.
Middle Atlantic MV-RR37 37-Space Rear Rack Rails Kit (1 Pair)

Middle Atlantic MV-RR37 37-Space Rear Rack Rails Kit (1 Pair)

11-gauge, 10-32 threaded, rear rack rails (2). All mounting hardware included.
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Usually ships in 6-10 business days.
Middle Atlantic MW10FT 10" Fan Top (without Fan)

Middle Atlantic MW10FT 10" Fan Top (without Fan)

Top options accept 10" fans for active thermal management.  All tops include a removable two-space service plate that allows removal of top without disrupting cable bundles.
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Usually ships in 6-10 business days.
Middle Atlantic MW-ST Solid Top Rack Panel (for WRK, MRK, VRK Series Racks)

Middle Atlantic MW-ST Solid Top Rack Panel (for WRK, MRK, VRK Series Racks)

The Middle Atlantic Products MW-ST is a solid top that includes a removable two space service plate to allow removal without disrupting cable bundles.
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Usually ships in 2 business days.
Middle Atlantic MW-VT Vented Top Rack Panel (for WRK, MRK, VRK Series Racks)

Middle Atlantic MW-VT Vented Top Rack Panel (for WRK, MRK, VRK Series Racks)

Slot pattern-vented tops include a removable two space service plate that allows removal without disrupting cable bundles.NOTE: The picture above is not the slot pattern-vented top rack panel, but shows how the top can be ...
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Usually ships in 4 business days.
Middle Atlantic MW4FT 4-1/2" Fan Top (Excluding Fan)

Middle Atlantic MW4FT 4-1/2" Fan Top (Excluding Fan)

All MW series tops include a removable, aluminum, 2 rackspace service plate, which allows for easy drilling for cable bundle entry or use of rack panels (shown removed for clarity). The MW-4FT and ERK-4FT feature laser knockouts for up to ...
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Usually ships in 6-10 business days.
Middle Atlantic HP24 100 12-24 x 5/8" Phillips Screws with Nylon Washers

Middle Atlantic HP24 100 12-24 x 5/8" Phillips Screws with Nylon Washers

Primarily used in telecommunications and data, these 5/8" long 12-24 thread screws are heat-treated to prevent head stripping. Black oxide finished, comes complete with nylon washers.
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Usually ships in 6-10 business days.
Middle Atlantic TBIT Star Post Bit for Driving HTX Security Screws

Middle Atlantic TBIT Star Post Bit for Driving HTX Security Screws

Middle Atlantic's TBIT is a star post bit for driving HTX security screws.
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Usually ships in 2 business days.
Middle Atlantic SW Shoulder washers, 100 piece

Middle Atlantic SW Shoulder washers, 100 piece

When used in conjunction with the stock washers supplied with all our screws, these black nylon shoulder washers help prevent ground loops. 100 piece count
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Usually ships in 3 business days.

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