4-Position Adjustment Bracket (nylon) 9 3/8" x 1/2" W. This part may be screwed or riveted to the frame (attachments not included). Stainless self tapping screws are suggested. The screw holes are recessed. The screw size would depend on the frame hole size. If you are replacing the exact same bracket the holes should match up. If they do not you can use the bracket as a template to mark and drill new holes. Make sure that the two brackets are lined up the same on either side of the frame. Made to fit over round tubing. Three holes for attachment and each hole size is 13/64". Center of top hole to center of middle hole is 4.25" center of middle hole to center of bottom hole is 4.5". The four adjustment openings fit over tube sizes up to 1-5/16" diameter.