Amarine-made Rod Holder & Cup Holder As One , 316 Stainless with Round Top- with Drain at bottom 15 degree Rod Angle Amarine-made Rod Holder & Cup Holders ,The Inner diameter of Cup - 3-3/8" ,Rod holder with Drain on Bottom and Cup holder on Top, In One function as a standard cup holder and fishing rod holder combined. Amarine-made Rod Holder & Cup Holders In One are heavy duty, made of stainless 316 , built to last. Amarine-made Rod Holder & Cup Holders In One are available with 90 /30 / 15 angles and are suitable for installation anywhere along the gunwales, on leaning posts etc. , save your boat space Amarine-made Rod Holder & Cup Holders In One do more than just improve the way your boat looks they are also the solution to the age-old dilemma of what to do when a fish strikes and you have a drink in your hand. Rod holder with Drain on Bottom and Cup holder on Top, Vinyl liner (protect the rod ) has 1-5/8" ID.