Package includes 200 x Red Shrink Connectors 180 x Blue Shrink Connectors 80 x White Shrink Connector 40 x Yellow Shrink Connectors Functionality: Polyolefin outer tube and hot melt adhesive inner design create a long lasting waterproof seal between wire and connector. Waterproof connectors would prevent corrosion even in the most humid environments. Functionality: Transparent sleeve on butt connectors provides visual inspection. ---You can monitor the operating temperature and heating time. Easy identification: different colors for different connector sizes Can be perfectly used in marine and automotive applications. Functionality: Solder and seal connectors allow you to use them in hard to reach environments or in limited spaces. Since there is no crimping required, simply place the stripped wires into the solder sleeve and apply heat to complete the connection. A simple one-step wire connection, insulated and sealed. Function: Insulation protection: used to seal wire connections, prevent electrical leakage, and keep circuits away from rodent nuisance. The solder ring, when heated, melts and flows into the wire connection, effectively preventing the connection from breaking. How to use: 1.Pass a wire through the appropriately sized butt connector tube, connect and process the wires properly, and move the connector so that the solder ring section is aligned with the wire connection; 2.Heat both ends of the tube with a heat gun to make them shrink. Waterproof rings when heated become waterproof rings; How to use: 3. Heat the solder ring with a heat gun until the ring melts and penetrates the wire connection; Warning: Heat the heat shrink tube section until it shrinks tightly around the wires; Excessive heating will completely melt the heat shrink tube. The solder ring must be fully heated to penetrate the wire connection. ------Provide you with qualified terminals and meet your needs in a variety of wiring projects Whether you're working on your boat, vehicle, home, or scientific project, our heat shrink solder seal connectors will ensure a strong solder, increased current flow, and leak-proof connections every time.