Thumb Trainer 42 Closing the Cobalt lands you

Closing the Cobalt lands you in the stratosphere of grip strength

Sturdy 275 lbs test tactical cord can be attached to a loading pin or looped/snagged/clipped to anything you can imagine (color varies)

then try to hold it shut with one hand

For example

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

Thumb Trainer 42 Closing the Cobalt lands youSpring 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