Extending base - Expands from 2.5 to 3.75 inches in diameter to fit a wide range of automotive cup holders. Suitable for golf carts, boats, and trucks. The extra thick pads on the expanding base help keep the adapter securely in your cup holder. Nest slot for easy handling - Easy to remove from the nest by hand. The cup holder features a deep base to provide stable balance for your water bottle. Krubber tabs for bottles 3.2 to 3.8 inches in diameter - Tabs are made of a registered material selected to facilitate the addition and removal of bottles from the adapter. - This design helps ensure the adapter stays in your car cup holder when you remove the bottle to take a drink. - Includes 8 pillow foam pads to help maintain balance. - Additional sponge pads are included and can be glued to the lower half to fill the gap between the cup holder and the car’s cup opening, improving stability. Itals stability - Overall stability is enhanced through the combination of the expanding base, padding, and gap-filling pads. Use scenarios - On a golf cart, the extender fits a variety of bottle sizes, keeping drinks secure while driving over uneven terrain. - In a boat, the adjustable diameter and extra padding help prevent spills when the vessel rocks. - In a truck or car, the 3.2 to 3.8 inch bottle tabs provide a snug grip for tall bottles, with padding and gap-fillers improving balance and reducing movement.