This adjustable drink holder is specifically designed to fit an electric mobility chair. This product features and inner ring that can be flipped up or down to hold smaller and larger drink containers respectively. Smaller containers include things like soda cans and 20 ounce plastic bottles, while the larger containers are things like mugs, larger bottles, and a 12 ounce can with an insulated sleeve. This product mounts under the armrest of your electric chair using the SnapIt! System. The inner diameter of this cup holder is 3.62" and the overall height is 3.95." You must choose whether you want this cup holder to fit on the left or right side of your mobility device. This product is made of high density polyethylene – a highly durable material that will never chip or break. If somehow this accessory does break or chip, simply utilize this product's warranty to recieve a new or repaired cup holder, just pay shipping.