Keep a variety of ferrule sizes on hand. These ferrules add strength and stability to stranded wire, protecting it from damage. They also make it faster to insert the wire into terminal blocks. Use a crimper (not included) to install wire.

Barrel-insulated ferrules have a plastic cover to prevent short-circuiting with nearby wire. Nylon-insulated ferrules are more durable and resist chemicals better than polypropylene.

Noninsulated ferrules allow you to easily inspect the wire connection.

Use ferrules for two wires to insert two wires into one terminal block.