Designed to accommodate Bass Pro Shops Rod Holders (sold separately), the Side and Flush-Rod Holder Mounts are an affordable way of ensuring your rod holder is securely mounted in the most convenient location. Perfect for kayaks, canoes, and other types of popular fishing boats. Mounting dimensions for both mounts: Holes are 3-1/8 on center from left to right and 1-1/4 on center from top to bottom. Requires a mounting surface of 3-7/8 x 2-15/16. Flush mount needs 1-5/8 clearance under the mounting surface. Available: Side Mount, Flush Mount. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Mounting Bases.