High impact thermoplastic Push-in design Captive locking wedge secures cable with single squeeze of standard electrician's pliers Provides excellent insulation, strain-relief and high pull-out value For use with 10-3, 12-3, 14-3, 10-2, 12-2, 4-2 NM cables. For use with multiple (2) 12-2 and 14-2 NM cables. For use with single and multiple flexible cords in wire range .300 in. to .600 in. 50/box.