Step down Heat Shrink butt splices are used to connect different gauge wires together. They are also used to connect multiple wires of the same size. So, you could connect a 10 gauge wire to a 12 AWG wire or connect a 12 AWG wire to two 12 AWG wires. The first step is to make sure you have properly stripped the wires to the correct length. If you look inside the butt splice you will see an indentation your wires should butt up against. Also, be careful to make sure that the butt splice and the wires insulation are touching. If not, you run the risk of weakening the connection. Next, the stripped wire is inserted into one side of the butt splice and crimped with the proper tool. This crimp bends the connector around the wire. This crimp creates a solid connection. On the other side, we'll add two wires. After crimping, proform the tug test to make sure the wires don't pull out Once your wire has passed the test, apply heat to the heat shrink working outward. Be careful not to burn the butt splice or the wire insulation. Now you've created a durable, environmentally protected connection. Remember, Butt splices are useful for their rapid installation and durability. Other methods of connection may not offer the same level of protection.