Tiger Shark Ultratac Jumbo Size Putter Grip Black Oversize or jumbo design that helps reduce grip pressure for a more natural release to improve putting stroke Keeps wrists stable through impact, promoting a uniform shoulder motion for improved distance control .580" core diameter - installed size 110 grams "I have found that the Tiger Shark grips give me a better (more stable) feel and the grip weight shifts the balance point up the shaft for better control compared to the popular "round / soft" grips."