This Truth Hardware Maxim Multi-Point Casement Window Lock has a sleek, low-profile design that will not interfere with curtains or blinds. This window lock has excellent "reach-out" capability. No need to fully close the window before locking it. Just close the window within 5/8" and acuate the lock handle. Used by several window manufacturers. Requires a mounting cutout of 1/2" x 4-3/8".The recommended screws are 2 pieces of #10-24 Phillips, Pan Head, Thread Forming Machine Screws.