Chrome plated zamac slide latch is surface mounted with 2-3/4" hole centers. The offset bar is needed when the door and pilaster are of the same thickness. (Related parts: 21-017, 21-123, 21-019, 21-100). Used by Ampco, Bobrick, Capitol, and Comtec brand partitions. Please see the "Related Products" tab and click on the pictures shown above for detailed measurements.