Middle Atlantic's LL-VC21-4 is a 4 pack of vertical channel lever locks for use with Lever Lock compatible racks (BGR and BGR-SA). Lever Lock is a "TOOL FREE INTERNAL MANAGEMENT SYSTEM". These 21"H channels lock in place and are designed to effectively manage your cables by simply lacing cable bundles from top to bottom, and again, no tools or hardware necessary. The patent pending Lever Lock design maximizes space while minimizing the amount of time needed for installation and servicing.