Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Wrist and finger exerciser

I like this because of the way you can work just your fingers, if you have circulatory issues with your hands this might be a good choice. The rubber pad gives you the ability to changes the position in a variety of ways to be able to hit each finger in several different positions. You can place one finger over one or two of the spring loaded pads to get a different tension for your workout. Of course there are 3 more lower tension devices in this line to select from.