Made of high-quality brass and steel material which is corrosion resistant with excellent electrical conductivity that can reduce voltage distortion and transmission loss. And it has 4 ports for multiple cable connections, wiring is easy and convenient to modify. Positive and Negative is clearly labeled on the battery terminal connectors that you can easily recognize. Our battery terminal connectors are compatible with cars, vans, caravan, tachts, trucks, pickups, buses, etc. Works on round post auto batteries SAE/JIS Type A posts. Please be sure to connect correct terminal to correct polarity. Equipped with a hex wrench which can help you to complete installation more convenient and easier. And it only takes a minute to clean, use the terminal cleaning brush that we provided to clean dirt, debris and corrosion. The products included can fully meet your need. Package contains 2 battery terminal connectors (positive and negative), 4 insulation sleeves, 2 battery terminal cleaning brushes, 2 battery anti-corrosion washers and a hex wrench.