Odyssey Men's White Hot XG 2.0 2-Ball Putter Multi-Layer Insert: Constructed from a soft elastomer core thats highly resilient for exceptional feel and truer roll. A thin, firm outer striking surface infused with urethane provides fine-tuned responsiveness. 2-Ball Alignment System: Makes lining up putts easier and more accurate The insert also allows weight to be shifted to the perimeter of the head for a higher MOI and better stability.