The D's Locks hub lock system is a revolutionary wheelchair brake substitute. These hub locks for manual wheelchairs take the place of traditional push-pull or scissor style brakes. The benefit of D's Locks is that they work independently of the tire by locking the wheel at the hub. Therefore tire types and air pressure no longer affect your ability to remain stationary. With one lever, both of your wheels can be locked securely in place simultaneously. D's Locks mount completely out of the way, so thumbs stay intact. Additionally, the brakes are no longer the widest part of the chair. In most cases they add little to no width. D's Locks can be installed in less than an hour. No special tools required!