HWMSR12U is a pair of 19-inch square hole panel rails sized for 12U HWM Series swing-out wall-mount rack cabinets. It is intended for IT, telecom and structured cabling installers who need square hole (cage nut style) mounting instead of tapped 10-32 rails, so servers, switches and patch panels supplied with cage nuts and cage nut screws can be installed in an enclosed wall cabinet.

The rails are formed from mild steel with a painted black (thin) finish, and each rail carries U-marking so rack unit positions can be identified quickly during equipment layout and future service visits. The set is sold as a pair and mounting hardware is included, so no separate fastener kit is required to attach the rails inside the cabinet.

Drawing dimensions for HWMSR12U show a 12U rail with a 20.50 in (521 mm) 12U marked length and an overall rail dimension of 21.03 in (534 mm), matching the 12U cabinets in the HWM Series ordering table (HWM2412U20 and HWM2412U26 models). Shipping weight for the pair is 5 lbs (2.27 kg).

Within the HWM accessory range, the 12U cabinet can be fitted with either the HWMTR12U tapped 10-32 rail pair or this HWMSR12U square hole rail pair, alongside the HWMRPP12 rear-pan panel for post mounting. The part is made in Canada, is USMCA compliant, RoHS and REACH compliant, and is listed under UL File # E474597 with standards noted as cULus, PCI, Zone 4 and TAA-compliant.