IAenclosures 2U Universal 5" L shaped Rear Mount / Center Mount Bracket for 4-post 19" Server Cabinet (RCB1067-S 5.4") Fits in to any standard EIA-310 19" & 23" 4 Post rack 16 gauge galvanzied steel Vertical rail side supports rack screw #10, #12, M4 and M5 Size Adjustable up to 5" in depth 9 Oblong holes.