Prime-line part F 2912 is a window sash lock for use on single-hung and double-hung vertical sliding windows. This item includes a sash lock, keeper, fasteners, and easy-to-follow installation instructions. These white-painted locks are constructed of diecast and fit windows manufactured by crystal windows. The locks and keepers are coated with a corrosion-resistant, long-lasting painted finish. Prime-line sash locks like these are used nationwide, but they are typically found in homes and apartments in new york and Pennsylvania. Sash locks like these are used by many to replace damaged or missing locks and install them easily with a simple Phillips head screwdriver.