Thumb Trainer 42 then try to hold it

then try to hold it shut with one hand

consider shortening your working sets to 2 or 3 sets and performing a few negatives with the challenge gripper

For example

Also available: RB 250 (Aluminum) and RB 250 (Scarlet)

Two half turns (180 degrees each) count as one FULL revolution

Thumb Trainer 42 then try to hold itSpring loaded masterpiece Stainless steel and wood spring loaded thumb isolation trainer made by grip community legend EatChalkGetBig. Comes with three springs that take around 15, 30, and 45 lb of force to compress the thumb pad flush with the handle. Over tightening can slightly increase the resistance, and under tightening can slightly decrease the resistance. Interchangeable springs Change springs by twisting to unscrew the inner plastic ring from