PRODUCT DESCRIPTION The terminals themselves are made of brass, and the fasteners are made of stainless steel to provide maximum waterproof and battery acid protection while providing the electrical connections required to operate electronic devices. TIGHTEN IT NORMALLY, IT WON'T FALL OFF EASILY！ FEATURES:  1. The battery terminal connector is made of brass. Better corrosion resistance. 2. Used for battery extension, parallel connection, and ground connection. 3. Tool-free quick-release battery main line wiring terminal, stable connection, reduce current consumption. PACKAGE INCLUDES:  1 pair of Positive and Negative Copper Battery Terminal Connector （1 pair = 2 PCS）+1*L wrench +4* terminal block. FULL GUARANTEE INCLUDED 📦 Insured Worldwide Shipping: Each order includes real-time tracking details and insurance coverage in the unlikely event that a package gets lost or stolen in transit. 🔒 Safe & Secure Checkouts: We use state-of-the-art SSL Secure encryption to keep your personal and financial information 100% protected. If you bought it and felt that it is not for you, don't worry. We will make it right by offering you a replacement or refund. It 100% Simple & Risk-Free process. If you have any issues with our products or the delivery, we're happy to offer a REPLACEMENT or FULL REFUND, no questions asked!