The RackSolutions 3U Universal Server Rail Kit fits in most standard 4 post 19" racks and can be mounted in round, square, and threaded holes. The L bracket shape holds your servers safely up to 200lbs.
The rail kit depth is fully adjustable from 10"-31.75" (254mm-806mm) all by loosening the screws and nuts. The rail kit is made from 18 GA steel and is zinc plated.