Make sure your sliding patio door locks securely These sliding track locks not only work on patio doors, but you can use them to make sure your sliding glass door locks securely as well. These sliding patio door locks fit over the track of your gliding windows or sliding glass door; locks easily in place with its two thumbscrews. Sliding track locks can also be used to lock a sliding door or window in a slightly open position for ventilation, without compromising on security. You get 10 locks per box.