This is a cup holder specifically for attachment to an electric wheelchair. It is able to fit canned drinks and 20 ounce plastic soft drink bottles. This product is meant to be mounted under your electric wheelchair's armrest using the SnapIt! System – a highly versatile fastening system. Be sure to specify your electric wheelchair’s specific model when you order. This cup holder has an inner diameter of 2.9" and an overall height of 3.95."