The Atlas Sound TPS24-05 Telephone Power Supply features a compact size and light weight that lends to convenient installation almost anywhere. Wall mounting is easily achieved via mounting ears on the 6.75’ L model or with keyhole slots in the chassis of the larger 13.25" L unit. In addition, four rubber feet are provided on the 13.25" L models for secure shelf mounting. For attractive installation in 19" W equipment cabinets, an optional factory-assembled, black textured rack mount accessory shelf (Model PS-RK) is offered to support four 6.75" L units or one 13.25" L unit. The rack shelf comes complete with front viewing hole for the power indicator light of the 13.25" L models and knock-outs to accommodate line cords.