Iomic Large Size Putter Grip M58 Jumbo Golf Iomic Art series Iomic grips are made using high-pressure injection molding to achieve its superb quality. Using this method, they are able to achieve a truly consistent grip. The weight on each grip has a differential of plus minus 2 grams. The methods used to produce conventional rubber grips have a 5 to 8 gram margin of error. Iomic grips release a negative ion that increases blood flow in the hands, which in turn, promotes better feel and feedback in the hands during the swing. Iomic grips are the only grips that are UV protective for more durability Softest Grip on the market