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Hammond CLSR21U pair of 21U black square-hole 19-inch rack mounting rails with silkscreened U markings

Hammond CLSR21U 21U Square-Hole Rack Mounting Rails, Pair

Hammond Manufacturing|

MPN: CLSR21U

|

UPC: 623980795539

In Stock
$99.95

Ships from and sold by A5 IT

Ground Shipping · $34.99Arrives by Monday, Oct 26
Order within 3h 32m to get it by Monday, Oct 26
New, with full manufacturer warranty
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Key Features

  • Pair of 19-inch panel rails providing 21U of mounting space, 36.78 in (934 mm) per the drawing
  • 0.38 in square holes on typical EIA spacing for cage-nut mounting of standard rack equipment
  • White silkscreened U markings for fast, accurate rack unit counting during installation
  • Mild steel construction with painted thin film black finish
  • Listed as an additional optional mounting rack rail for CLC Series colocation cabinets
  • Matches the 21U per-bay layout of 2-bay CLC cabinets; CLTR21U is the 10-32 tapped alternative
  • Standards listing includes cULus, PCI and TAA-compliant; UL File # E474597
  • Made in Canada, USMCA compliant, ships at 10 lbs (4.54 kg)

CLSR21U is a pair of 19-inch panel mounting rails punched with 0.38 in square holes on typical EIA spacing, sized for 21U of equipment mounting. It is listed under the CLC Series colocation server rack cabinet program as an additional optional mounting rack rail, making it a practical add-on for data center, telecom and service provider teams who need extra mounting positions inside a cabinet bay.

The rails are formed from mild steel and finished in painted thin film black. White silkscreened U markings run along the rail face so installers can count rack units quickly and keep equipment aligned between the front and rear rail planes. The pair ships at 10 lbs (4.54 kg).

Mounting height is listed as 36.75 in (933 mm) in the series ordering table, with the drawing showing 36.78 in (934 mm) overall for the 21U span. The square-hole pattern accepts cage-nut style hardware used with standard 19-inch rack equipment; mounting hardware is not included with CLC Series rails.

CLSR21U corresponds to the 21U bay spacing used in the two-bay CLC cabinets, which provide 21U per compartment. A 10-32 tapped equivalent, CLTR21U, is offered for installations that prefer threaded rails instead of square holes.

  • Square-hole rail pair, 21U, for 19-inch rack equipment
  • Mild steel construction with black painted thin film finish
  • Covered by UL file E474597; RoHS, REACH and USMCA compliant, made in Canada

Ideal For

  • Adding mounting positions in colocation data center cabinets
  • Multi-tenant cabinet bays with segmented access
  • Service provider and telecom facility installations
  • Meet-me rooms and shared enterprise data centers
  • Separating equipment by department or business unit

Overview

SeriesCLC Series (Additional Optional Mounting Rack Rails)
Rail TypeSquare hole
Rack Units21U
Part NumberCLSR21U
Product Type19" panel rails with square holes (pair)
Short Description2B PNL RAIL 37" SQ HOLE
10-32 Tapped EquivalentCLTR21U

Dimensions

Rail Profile (Per Drawing)2.00 in (51 mm) x 1.02 in (26 mm)
Mounting Height (Ordering Table)36.75 in (933 mm)
Overall Rail Height (Drawing, 21U)36.78 in (934 mm)

Identifiers

UPC623980795539
ECCNEAR99
UNSPSC43223306
GTIN-1400623980795539
Tariff Code7326.90.8688
Country Of OriginCA
UPC W/o Check Digit62398079553

Rack Mounting

Hole Pattern0.38 in square holes, typical EIA spacing
Mounting HardwareNot included
Equipment CompatibilityStandard 19-inch rack equipment

Packaging & Shipping

Shipping Weight10 lbs (4.54 kg)

Construction & Finish

FinishPainted thin film black
MarkingsWhite silkscreened U markings
MaterialMild Steel

Compliance & Certifications

StandardscULus, PCI, TAA-compliant
UL File #E474597
RoHS CompliantYes
REACH CompliantYes
USMCA CompliantYes

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Frequently Asked Questions

How many rails come with CLSR21U?▾

CLSR21U is supplied as a pair of 19-inch panel rails with square holes.

What hole pattern do these rails use?▾

They are punched with 0.38 in square holes on typical EIA spacing, suited to standard 19-inch rack equipment.

How tall are the rails?▾

They provide 21U of mounting space. The series ordering table lists a mounting height of 36.75 in (933 mm), and the part drawing shows 36.78 in (934 mm) for the 21U span.

Is mounting hardware included?▾

No. The CLC Series specification states that mounting hardware is not included with the rack mounting rails.

Is there a tapped version of this rail?▾

Yes. CLTR21U is the 10-32 tapped 21U rail pair listed alongside CLSR21U in the CLC Series optional mounting rack rails table.

Where are these rails made and are they TAA compliant?▾

Country of origin is CA (Canada), the part is USMCA compliant, and the listed standards include TAA-compliant, cULus and PCI.