These aluminum mounting plates allow quick and easy removal of your Stationary or Lift Ladder. Stainless steel locking pins keep ladder securely in place. Also can be used on Flip-Up ladders if you permanently remove the flip-up mounting plates. Installation Note: The mounting plates have 4 holes so they are universal to fit several ladder brands including Dockmate and International Dock. For most ladders the front post will be positioned in the slotted hole and the rear post will go in the second hole from the slotted hole. The position of the post should be tested on your ladder before you mount the plates to your dock. The other two holes are used to mount the plates to your dock. For use with Stationary or Lift Ladders | Dockmate Dock Ladder Quick-Release Mounting Plates, Pair