Check the listing for details. CFF Build Bone Crushing Grip Hand Strengthener, 200-Pound. Condition: New. Listed at 12.99 USD. CFF Pit-bull Gripper If you want to develop serious hand strength for a sport, or just want to impress your friends, then Pit-bull hand grippers are the perfect choice for you. If you're worried about working hard, getting sore hands and possibly some calluses on your fingers, then this product is not for you. Our hand grippers were designed for developing incredible hand strength. To do this, you must train your hand similar to any other body part and use low reps(and only 2 to 3 times per week) You will not develop a super strong grip by doing a lot of repetitions. Like any other body part, don't forget to warm-up and stretch your hand. High quality aluminum-handled grippers Offered in 50 inch-force-lb. torque increments from 100 lbs. to 400 lbs. so that you can improve over time Allows you to build the huge forearms and crushing grip Easily transported so that you can train anywhere and at any time Extremely durable and long-lasting