From Manufacturer
The iStarUSA Sliding Rail Kit (20" / 508mm) consists of 2 solid ball bearing sliding rails and is designed make accessing your rack mounted equipment easier. It features a 3-stage temporary lock, which allows you to securely pull your equipment out in stages without having to extract the entire unit. Constructed from SECC steel that provides strength and durability, these rails are capable of handling system weights up to 85 lb (38.55 kg).
