Small Blue Heat Shrink Wire Connectors - With any low voltage lighting system, waterproof connections are crucial to maximizing the life of the system. A two-step installation process ensures a fail-proof connection in every installation. Each wire connector has two components: a tin-coated copper butt splice and an adhesive-lined heat shrink tube. You will need some direct-burial wire to make the connections. We have two-wire connector sizes. The small, blue connector is ideal for connecting one fixture onto the home run, or a small junction of four fixtures. The medium, yellow connector is best for splitting home runs with two #10-gauge (6.0 mm2) or three #12-gauge (4.0 mm2) wires.