The KF539 Rixen & Kaul Replacement Red Button With Lock is designed specifically for the KF860 Handlebar Adaptor, a versatile handlebar mounting system for accessories such as bags, baskets, and smartphone holders. The red button with lock serves as a release mechanism for the KF860 Handlebar Adaptor, allowing you to easily attach and remove accessories from your bike's handlebars. Made from high-quality materials, the KF539 Replacement Red Button With Lock is designed to be durable and long-lasting. The button features a locking mechanism that ensures your accessories stay securely in place while you ride, and the red color makes it easy to spot and operate even in low light conditions.