http://gripfaq.com/
Crush Strength: CoC grippers.
Pinch Strength: Pony clamps, Olympic Plates, A piece of wood with a loading pin
Wrist: Sledgehammer levering, Wrist roller.
Supporting: Timed holds, pullups (towel, rope, etc.)
Make sure to work open hand as well, it will prevent strength imbalances, and give you more "hand wellness". For this, get a decently strong rubberband and carry it around, and rep out within comfort throughout the day.
The search function is also useful, but IMO there's not much information beyond "I do blah blah blah."
Richard Sorin at a Martial Arts conference.
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