*Force resistance values shown represents a 3:1 safety factor. Aickinstrut Stop-Lock Assemblies reduce the chance of pipe slippage when running supports vertically. Stop-Locks are recommended for applications that are subject to vibration, have regular contact with fluids or are vertically mounted (Type 2). The Stop-Locks fit all three sizes of channel. Stop-Locks are offered with a 3/8", 1/2" and 5/8" bolt size. The 5/8" Stop-Lock Assembly is supplied with a heavy duty channel nut (the 5/8" Stop-Lock Assembly will not work with the 1000 Series Channel). The Stop-Lock Assemblies' components are manufactured from glass-reinforced polyurethane.