The Dell PowerEdge R620 Slide Rails can provide a stable, sturdy and easy-to-install sliding rail solution for Dell-compatible server racks. Dell PowerEdge R620 Slide Rails are compatible with standard 19" EIA-301 server racks, and can work with either 2 post or 4 post models. In terms of server compatibility, the slide rails are designed for the Dell PowerEdge R620, R420, R320. The device is designed to fit in racks using either standard square, round or threaded holes, and feature an adjustable mounting depth between 3" - 30" (76.2 - 762 mm). This rail kit is not a ball-bearing rail kit.