This bright polished 316 stainless steel surface mount boat seat cup holder allows you to keep a cup, or bottle steady while underway without having to cut a big hole. It mounts with a single stud (1-1/2" long) and has a second smaller post (3/8" long) to keep it from turning. The cast stainless base looks great, provides plenty of strength, and covers any nicks you may make in the gel coat when drilling the holes! To install, just drill a 1/4" hole for the stud and one for the post on 5/8" centers. Put it in place with a little sealant and tighten the washer and locknut (both provided) from below for a beautiful, clean appearance! Also great for hanging jigs and other fishing tackle to keep it handy!