Five-square Anti-theft Socket: This aluminium alloy handle works like a five-square socket spanner to lock the skewers, offering extra security against theft. Anodised treatment, quick release edge, copper seal, wear resistant, smooth, suitable for light vehicles. Easy Installation And Release: This mountain bike skewer can be attached to or released from the skewers via a bolt, offering practical convenience for cyclists. Can also be used as a survival whistle. Wide Compatibility: This bike seatpost clamp bolt is compatible with a variety of bikes, including road bikes, mountain bikes and folding bikes. Ultra-light, robust and high-strength. Sturdy Construction: Made from high-quality aluminum alloy, the skewer is strong, durable, and resistant to wear and tear. This robust design promises longevity and a dependable performance. Lightweight and Portable: The skewer is compact and easy to carry, making it a convenient tool for cyclists on the go.