With anti-slip rubbers, keep the bottle fixed inside, prevent them from spilling and falling Pontoon Boat, Bass Boat, Jon Boat, Jet Ski. The boat rail cup holder can hold bottles, coffee cups, beer, cans, glass, etc. Easily attaches to boat rails, can move the cup holders to any rail. Suitable for yacht, pontoon boat, bass boat, Jon boat, kayak. etc. The cup holders are easy to install, just tighten and go, no tools or assembly, no drilling required and no damage to the boat, mount on the boat aluminum rail, pole or bimini top rail. ABS plastic boat cup holder, the cup holder clip with non-slip rubbers, the grip is strong, attach to the boat rail, the 360 degree adjustable knob will make the cup holder firmly on the rail, you can put cup holders on it and don't worry about spilling everywhere. The boat cup holder is simple, unique, and practical. The large caliber cup holder can hold bottles of different sizes. The adjustable clamp allows 360 degree rotation, and it works great with