General description The Expandable Car Cup Holder Adapter is designed to fit most car cup holders, providing a secure and adjustable solution for holding various sizes of cups and bottles. Its innovative design includes an adjustable base and a silicone coaster to enhance stability and usability. Technical specifications Expandable base diameter: adjustable from 2.6 to 3.8 inches Compatible with bottles/cups of diameter: 2.9 to 3.88 inches Accommodates cup sizes: fits most 20oz-40oz water bottles Usage Simply rotate the adapter base to extend or retract it for a snug fit in your car's cup holder. The silicone insert allows for easy placement and removal of cups. The U-shaped slot design accommodates cups or mugs with handles without tilting or spilling. Other information Includes a removable base that can be centered or offset for different cup holder positions. One-year warranty included.