1. Upgrade Car Cup HolderThe bottom and top of the cup holder can be easily turned by the knob, and the cup holder can be easily removed from the slot. The rubber sleeve around the top of the cup holder firmly fixes the cup in place, and the car cup holder also has a locking button to hold the upper cup firmly in place. 2. 2IN1 Multifunction DesignThe double car cup holder expander can be divided into 2 cup holders by rotating the upper one, and can hold two drinks at the same time. The lower cup holder's diameter is 2.95', compatible with most thermos, beverage bottles/cups. The upper cup holder adapter can be extended from 3.0' to 5.9', which can hold larger bottles, cups, tablet PC and food like fried chicken and instant noodles etc. 3. Upgraded Adjustable Base The base of the upper cup holder can rotates 360 degrees ly. The position can be shifted and adjusted according to the space of the car body, which is the most comfortable place for you to reach your drink. The lower cup holder base is expandable from 2.2' to 3.2' in diameter to fit for most cars' ROUND CUP SLOTS, works great for cars, golfcarts, boats, trucks, and RVs. After the upgrade, the base is longer to be more stable while holding things. 4. and InstallInsert the base into the car cup slot; Rotate the cup holder expander to expand the bottom adapter and firmly fixed the base(DO NOT continue to rotate the cup holder base expander when it has been fixed on the car cup slot); This 2 in 1 car cup holder expander is suitable for most car cup slots, may not be compatible with certain styles of cup slots which is sharpangled. Please check carefully the product size before purchasing.