The Advantage Flush Mount is the most unique flush mount on the market. It incorporates a positive double cam lock, which ensures a quality hold on your gear, and is easily released with a unique push button lock. Many other manufacturers&'; products will fit into this mount as well. Comes with a rubber cap to keep the water out. Bolting dimensions are the same as most manufacturers&'; - Making it simple to just replace the mount Holds most manufacturers&'; products, too Positively locks gear in place Positioning every 30 degrees Not recommended for use with the F051 Adjustable Extension Post Requires a minimum of 1-5/8" hole size for the lock to function properly