The Heavy Grips™ hand gripper series was developed for athletes who want to take the training of their grip strength to the next level. These high quality aluminum-handled handgrippers are made in 50lb increments from 100lbs to 350lbs so that you can train your grip similar to training any other bodypart-- by increasing resistance. This will finally allow you to build the huge forearms and crushing grip you have been unable to achieve by doing endless reps with dept. store hand-grippers. If you want to develop serious hand strength for a sport, or just want to impress your friends, than the Heavy Grips™ hand grippers are the perfect choice for you!