Top Quality Copper Core - 350pcs butt connector kit, each connector is made of high-quality tinned copper tube, which ensures a firm connection, prevents short circuits, and will not loosen after long-term use. High water resistance of IP67, can be used for marine-level line equipment, resisting severe weather Waterproof & Seamless Solder - These butt connectors are made from polyolefin, feature a dual wall design, with a shrinkable outer layer and an inner which will melt into place when heat is applied to create a strong, watertight seal. Widely used in wire connection and marine grade connection Durable & Long-lasting - Each with a thick tinned copper barrel that resists corrosion to hold the wire tight when crimped, to a strong connection and brave all harsh climatic conditions and your wire will never out of the connector Visual Wiring - Translucent polyolefin tubing allows direct visual inspection of wire connections. The cable size is on each terminal, AWG 26-10, in eye-catching 3 colors for easy marking or identification of wire conditions Easy to Use - This crimp heat shrink butt connectors is very easy to use. , use crimping pliers to put the connector and wire into the slot for crimping, then use a heat to heat the tube so that the inner adhesive melting until it wraps the wire tightly kits are widely used in connection of holiday lights, boats, planes, trucks, , , motorcycle, fish finders and other wiring projects. Applicable to industrial electrical equipment, car/truck wire connect, boat or aerospace line equipment Note: due to different production batches, the plastic box style is random,'t accept the specified packing list:350pcs Heat Shrink Butt Connectors (Yellow x 32pc, Blue x 100pc, White x 68pc, 150pc) Colour:P Color Material:PVC Package Contents: 350 x 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.