HOW TO INSTALL YOUR RAIL MATE RAIL MATE will work on any size square tube railing on a pontoon boat. 1) Determine the location you would like to install. 2) Center clearance holes in RAIL MATE slide bracket on top of flat rail surface. 3) Mark location of hole. 4) Drill clearance holes for 1/4" bolts provided. 5) Fasten slide bracket to rail and tighten hardward. 6) Slide tongue that is connected to mounting pad into slide bracket on rail. Tighten hand knob to keep in place. 7) Mount which ever device or accessory you choose, sonar, rod holers, wifi speaker, to pad by locating holes and drilling through mouting pad. Use hardware as needed to secure. (not included) 8) You can remove the RAIL MATE by simply loosening hank knob and sliding bracket out. Makes storage and security easy! 9) The 3/8-16" threaded hole is for extra security and prevent loss. You can either thread bolt in place and install nut on threaded bolt (included) or even use a small pad lock. These can be used if you are not removing after each use. Of course the best method is slide out and stow!