The 4 post telecommunications are constructed of steel and capable of accepting 19 wide EIA equipment. The equipment mounting rails shall have tapped 12-24 style mounting and shall have rack unit markings. The rack shall accept shelves and equipment brackets. The front and rear structural posts of the rack shall be capable of mounting NetRunner or PatchRunner vertical cable managers and accessories, such as power outlet unit brackets. The construction method shall support up to 907kg (2000 lbs.) of equipment, cabling and ensure an electrically bonded structure for ease of grounding.