Cup Holder: The extendable base can be adjusted from 6.6 to 9.7 cm in diameter to fit various types of car cup holders. Simply twist the adapter base to extend or retract it, and it will securely attach to your car's cup holder. U-shaped Slot: This design is very practical, as cups or mugs with handles can be perfectly placed in this cup holder without tipping or spilling. Silicone Coaster and Insert: The silicone insert in the cup holder makes it easy to insert and remove cups from the adapter. The coaster ensures that the cup sits securely in the cup holder while driving, preventing it from shaking or falling, and preventing friction against the bottle holder. Durable Material: The main body of the cup holder is made of ABS plastic, making it lightweight, durable, waterproof, and easy to clean. Suitable for Various Sizes: The silicone splitter allows the adapter to work with bottles/mugs from 7.4 to 9.8 cm in diameter. The extended cup holder fits taller and larger cups, providing greater stability and less wobbling. It also fits most water bottles from 591 ml to 1134 g.