Chrome plated zamac wrap-around hinge mounts on a 1-1/4" square pilaster. Mounting holes are 1-1/2" on center. Dimension is 1-1/4" from back-plate to center of hole. (Related parts: 21-008, 21-201, 21-158). Used by Flush Metal, American Sanitary, Fiat, Atlanta Sunbelt brand partitions. Please see the "Related Products" tab and click on the pictures shown above for detailed measurements.