How can I strengthen my forearm grip?

There are three main ways to strengthen your forearm grip: fingerboarding, using pinch or crimp blocks, and recruitment pulling on an immovable object.
 
Transcript: "How can I strengthen my forearm grip? So seeing climbing, there are several ways you can do this. Probably the most obvious one is the one that most climbers use is a finger board. This is a device climbers, put above their door frame, usually in their homes, they can hang off that they can do, pull-ups offer, they can do a number of different exercise on it. Usually there is lots of different types of holds on the fingerboard edges and Pockets. Sometimes it's up to just one Edge and it's very simple but this is probably the most common tool. Climbers, use a second tool, climbers. Use our pinch or crimp blocks. These are literally blocks of wood or plastic that you can attach, wait, to and do a sort of dead lift off the ground in a variety of different grips. I would say, this is not as specific to actual fingerboarding because you're not in a hanging position. However, it is a little bit more targeted to specifically the Forearm muscles because when you're hanging, your utilizing, your shoulders, your biceps, your lats, whereas literally just lifting something off the floor, it's just a little bit more specific to the forearms. The third and probably least popular tool but possibly the most interesting is simply doing something called a recruitment pool and you can use this on any of what I've just said. I think. A board or a pinch block, cross block and but you need to have it attached, something that's immovable. And there you just engage in the crimp position and kind of pull as hard as you can without any other part of your body. Other than your forearm and I use a device called a tin deck. T.i. n DEQ, that is a load cell attached to the device. And that way I can measure the force generated from my forearm specifically."