OP Fitness Silicone Barbell Grips - Arm Strength Builder Convert barbells, dumbbells and chin-up bars into THICK BARS so you can train the way pro athletes do to achieve real arm strength. Fit tightly around barbells, dumbbells and chin-up bars and won't move or compress Train like many athletes, crossfitters, military, MMA Fighters, and weightlifters to achieve explosive workouts Made from a rubber-like high-density silicone compound