PRIME-LINE E 2121 Mortise Lock - Adjustable, Spring-Loaded Hook Latch Projection for Sliding Patio Doors Constructed of Wood, Aluminum and Vinyl, 3-11/16?, 45 Degree Keyway, Round Face , Zinc Product Description When your sliding door mortise lock is broken or old, don?t replace the door entirely, just get a new mortise lock! This PRIME-LINE E 2121 Mortise Lock has an adjustable, spring-loaded hook latch projection for surface-mounted sliding patio doors constructed of wood, aluminum and vinyl with handle sets with 45-degree angled keyway positions when in the locked position. It also fits doors using W F manufactured handles. The mounting hole centers of this lock measures 3-11/16 in. from center to center, and the rear housing corners are square. Selection Tip: To ensure the perfect match is selected prior to purchasing, the lock will need to be removed to compare the following 4 features (besides the width of housing): 1) The distance of the mounting holes measured from center to center, 2) The faceplate ends; rounded or square, 3) The position of the slotted keyway when in the locked position; at 45-degree angle or vertical, and 4) The shape of the housing corners at the rear; square or slanted. Installation Tip: Watch the manufacturer?s How-To Video that is linked to this item page. From the Manufacturer This patio door mortise lock is constructed from steel. It features adjustable hook projection and a round end face plate. The keyway rests in the 45 degree position with the hook fully extended. This style lock is used on Adams Rite doors. See model number E 2187 for stainless steel. Features REPLACE OLD OR BROKEN DOOR LOCKS ? When your sliding door mortise lock is broken or old, don?t replace the door entirely, just get a new PRIME-LINE E 2121 Mortise Lock! FOR SLIDING DOORS ? This Mortise Lock can be used on sliding patio doors constructed of wood, aluminum and vinyl. Also fits doors using W F manufactured handles. EASY INSTALLATION ? Installation is quick and easy ? working sliding door locks are well within reach. Mounting Flanges have 6-32 tapped thread. 45 DEGREE KEYWAY - This E 2121 mortise lock has a 45-degree angled keyway position when in the locked position. PRODUCT INFO - The mounting hole centers of this lock measures 3-11/16? from center to center, and the rear housing corners are square. Mortise lock dimensions are: 1.125"(D)x0.5"(W)x3.688"(H). USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.