321 STRONG Hand Strengthener Ring for Finger Strength and Stress Relief Premium silicone hand exerciser measures 3.5 inches wide , is 0.8 inches thick , and provides up to 45 lbs of tension Exercise your forearm muscles all day long under your desk at work , workout tension and stress with this easy hand trainer Perform isometric stretching , hand crunches , and finger pinches Ring shaped hand grips are the perfect size for correct ergonomic form , so it is comfortable to use and limits fatigue Enhances hand grip performance in almost any sport and makes great gifts for the athletes in your life Made from 100% Grade A silicone rubber Measures 3.5 inches wide, 0.8 inches thick Provides 45 lbs of tension Perform isometric stretching, hand crunches, and finger pinches Perfectly sized for correct ergonomic form, so it is comfortable to use and limits fatigue Exercise your forearm muscles all day long under your desk at work Work out tension and stress Enhances hand grip performance in almost any sport Makes a great giftfor the athletes Easily transported, so you can take it anywhere