W&F style mortise lock - face has round end with vertical slot when locked.
Squared off lock body with flat mounting plate Installed with 6-32 machine screw;
7/8" Backset
Internal latch for primarily metal glass sliding patio doors;
Note: wood & vinyl doors usually use the 15142 with 45 degree slot.
Faceplate: radius corners / round ends
Installation Screw Holes: 3-11/16 inch center to center
Lock Body: 1/2 wide, 1-1/8 deep, 3-3/16 length
Keyway Slot: vertical when locked

Related Parts:
15142: 45 degree Keyway Slot primarily for wood and vinyl patio doors

Note: See additional pictures for dimensions

VIDEO: How to Replace Single-Hook Lock (part # 15143) in a Sliding Door