This CRL Glass Door Lock with Indicator is an attractive and practical way to add security and privacy wherever 5/16 to 1/2 inch (8 to 12 millimeter) glass doors are used in Glass-to-Wall or 180 Degree Glass-to-Glass installations. A turn of the thumbturn on the interior side of the Lock changes the color of the exterior indicator. Emergency access is made possible by a low profile screw on the exterior face. The Lock comes with a wall mounted strike plate, screws, and anchors. Both Lock and Receiver, used for glass-to-glass installations, come with gaskets and hex wrench.