●STRONG CRIMPS - Thick, seamless butt connector barrels ensure super strong crimps, and prevent your wire from slipping out. ●EXCELLENT CONDUCTIVITY - Pure copper ensures the highest conductivity. A thin layer of tin will protect your butt splices from corrosion. ●A VARIETY OF SIZES - This versatile kit includes uninsulated butt splice connectors for 24 to 8 gauge wires. ●HEAT SHRINK TUBING RECOMMENDED - For best results we recommend insulating your connections with dual wall, adhesive lined heat shrink tubing. ●LIFETIME WARRANTY - All Wirefy electrical connectors are backed by our best-in-class lifetime warranty. Our stellar customer service team is here for you to help with any questions.