... is solved.1. An elegantly simple locking mechanism, open or close is securely, easy and quick. Simple locking mech anism, ... do not use special tool to open or close the lock2. Easy wire changes, low friction & force, ... . No painful, not to be hurt the toothOpen or close, the force is on the bracket. It will not ... hurt the tooth Orthodontic self ligating brackets with perfect clip 0.022/0.018