GLASS LOCK 4 WAY 1 SIDE KNOB - G TO W A glass lock 4 way 1 side key and knob is a type of lock that is used to secure a glass door or panel with four possible orientations and a key on one side and a knob on the other. It is usually made of stainless steel or aluminum alloy and requires a cutout in the glass. Specification : 1) 1mm Thickness of Cover Plate, 2) Can be Fitted in 12mm Glass, 3) 3 Computerized Brass Key, 4) One side key & One side Knob, 5) Big Oval Design, 6) 4 Way Locking System, 7) Useful as Door Lock and Sliding Lock