About this item: BETTER WATERPROOF SOLUTIONS: Double wall design, Hot Melt Adhesive inside ensures wires strongly connected and prevent wires slipping from the terminal; Polyolefin outside tubing provides insulation and improves pullout strength. PREMIUM COPPER CORE: Heat Shrink Butt Connectors features a thick tinned copper barrel which ensures strong secure crimping every time. Thick copper barrel provides minimal voltage drop, high current flow and less heat. These will prevent short circuits and and make your connection projects and better. DURABILITY: Each connector with a thick tinned copper barrel that resists corrosion to hold the wire tight when crimped. The barrel is created from one seamless piece of copper that eliminates the problem of the barrel opening. Your wire will never out of the connector. EXCELLENT WIRE CONTACT - The copper barrel provides increased current flow, and ensures less voltage drop, preventing wiring failures and reducing equipment downtime. WIDE APPLICATIONS: Excellent stability, water resistance and electrical conductivity provide durable connection for motorcycle, off-road vehicles, lawn , , fish finder and marine application. Widely used on multiple projects of your Christmas lights, ships with high waterproof requirements motorcycle stereo, boat electronics, equipment switches. THICK COPPER TERMINALS 1.0mm for 12-10 AWG 0.8mm for 16-14 AWG 0.7mm for 22-16 AWG Note: due to different production batches, the plastic box style is random Color: As Shown Material: PVC Package Contents: 210 PCS Heat Shrink Butt Connectors Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.