Nylon zip ties are constructed with fire-resistant materials. Locking teeth in the cable tie head secures cables or wires. A zip tie works rather like a belt, where the end is passed through a buckle and fastened with a prong inserted through a hole in the strap. In the case of most conventional zip ties, the strap is passed through a head that includes a flexible tongue that glides over teeth, or serrations, molded into the strap to prevent it from slipping backwards, once applied. The cable tie has self-locking & one-piece construction which ensure fast & easy installation. Non-releasable cable tie, once locked cannot be opened or reused.