20pcs 4 AWG Gauge Copper Lugs w/ RED & BLACK Heat Shrink End Ring Terminals Wire Product Features High Quality: All the ring terminals are made of annealed electrolytic grade copper for maximum conductivity. All the shrink tube is well made of high-quality material, thick and durable. They are both for up to 600V, 257 degrees Fahrenheit which ensures its safe and relia. Reliable: These terminals have a close-end pad design, flared opening for easy wire insertion. Size is stamped on the pad, easy to identify. keeping electrical components, batteries, and cables safe and free from moisture, and also preventing solder from leaking during installation. Wide Appliance: Ring terminal wire connectors great suitable for distribution boxes, cars, RV, electrical wirings, and solar panels electrical applications. Keep Organized: Come with a storage plastic box, you can throw the kit in your toolbox and not have to worry about sizes getting mixed together. Product Specification MaterialCopper ConnectingCrimp-type Ring Size3/8 " Wire Input Size4AWG (gauge/ga wire connectors) Package Included 10 x 4AWG 3/8 "End Ring Terminal 10 x Heat Shrink Tubing 1 x Storage Box