Járngreiper was a tool in Thors arsenal. When wearing them Thor could wield his powerful hammer Mjolnir with exceptional precision. They provided him with an enhanced grip and control over his weapon.
Now you can wield Járngreiper for your own workouts to improve your grip and wrist control. When great power is called upon you can now rely on the Járngreiper wraps to help you control and isolate it.