Commercial Grade - Thermoplastic Vinyl Plugs Solid brass plug blades are firmly embedded in body. Terminal screw clamps are designed to contain wire and prevent binding. Terminal screws backed out – ready for wiring. Terminals in individual chambers to positively insulate conductors. Vinyl angle plugs have eight possible positions for maximum convenience. Combination slot/Phillips head mounting and terminal screws ease installation with power screwdrivers (Slot/Robertson screws in Canada where available).