Fat Gripz | Ultimate Arm Builder w/Serious Steel Fitness Carrying Bag | Sold as Pair! Fat Gripz Ultimate Arm Builder w/ Serious Steel Carrying Bag Fat Gripz are used by thousands of athletes and military, including many Special Forces soldiers, NFL players, top MMA fighters, champion bodybuilders (including Mr Olympias, Jay Cutler and Phil Heath) and CrossFitters Made from a rubber-like military-grade high-density compound - they have a slit on one side which allows them to be pulled open and when they close they will fit tightly round barbells, dumbbells and chin-up bars and won't move or compress Using a thicker handle stimulates much more muscle activation in the forearms and upper arms which leads to bigger muscle and strength gains thru the arms and whole upper body 100% Authentic Fat Gripz!