CRL Track Plunger Locks install easily on sliding glass doors in showcase track assemblies. They can be mounted in the H-Bar or within the surround frame of the glass doors. The spring-activated design permits keyless locking by simply pushing the plunger. Lock comes complete with two brass keys and trim washer. Customers needing duplicate keys can order Cat No. LKEY which is the blank key for this Lock. If these Locks are being used with D610, D5610 or MC610 H-Bar, the glass will require notching. If being used with LK610 H-Bar and D602 Lower Track, no glass notching is required.