Installs quickly into square hole, 4Post racks - Rackmounts a variety of equipment - Tool-less rack rails install in seconds - 45 lbs, 75 lbs or 200 lbs capacity (1U, 2U, 3U) Dell, HP, Apple & IBM compatible - Alternative to OEM slide rails - Mounting depth from 28 - 30" (711 - 762 mm) - Tool-less, cable management bar included - Work with square hole, 4Post racks 2Post rack mounting - Center mount installation also requires 2POST-2UKIT - Flush mount installation also requires 4UKIT-003