Grip strength is usually an athlete's first indication of fatigue when training . Harbinger's BIG GRIP bar grips will help you train your muscular endurance in a way that will improve functional grip strength. Our BIG GRIPS convert barbells, pull-up bars & cable attachments into "thick bars". Thick bar training activates more muscles when lifting, and builds bigger, stronger arms and upper body faster. Weightlifting and bodybuilding pros have used thick bar training for decades, now you can too! Made from a proprietary high-density compound, Harbinger BIG GRIP bar grips attach to the bar like a clamp and don't compress --even when dead lifting extreme loads. Easy to clean and transport so you can use at home and at the gym, and everywhere you lift.