Window stay locks are a useful security addition for your casement windows. These window locks are fitted to your window stays in place of a standard lug. The locking nut is then tightened in place with the locking Allen key supplied. Window locks are easy to fit and a great solution for locking your windows. Choose the black or pewter to match our range of Pear Drop, Shepherds Crook & Monkey Tail Stays. The window stay with Armor-Coat® co-ordinates with the Stonebridge Window Stays.