This CRL Adapter Block is commonly used with the Regular Prima Series (not Junior or Senior), Cardiff, Shell, and Rondo Series Hinges. The Adapter Block allows the hinge to be mounted directly into the Shower Deluxe Header Assembly and can be adjusted laterally to any position required. The Adapter Block has a clearance notch which allows it to fit under the wall bracket when the hinge is mounted close to a wall. A drilled 3/16" (5 mm) hole in the header is required for installation and the hinge base plate must be removed to mount the hinge to the header. Each Adapter Block is individually packed with a screw.