Finger boards

[Blinky]

I know you are but what am I?

 

[Murph]

I wouldn't recommend a finger board for building wrist and hand strength. They are primarily designed for building contact strength for rock climbing. As mentioned earlier the risk for tendon injury is very high. You might be better off to get a pair of training gymnastics rings like "elite rings". There are plenty of exercises that you can do with them and you pretty much can't beat a muscle up for working your entire upper body.