FXLuminaire® WCHSMD20 Medium Wire Connectors with Heat Shrink Wrap Adhesive-filled heat shrink tubes protect fixtures from damage and optimize system performance by ensuring a secure wire connection. Waterproof and rated for direct burial, medium connectors are ideal for splitting home runs with two 10 AWG (6.0 mm2) or three 12 AWG (4.0 mm2) wires.