The Ping Vault Bergen Stealth Putter is Fully Machined, 303 Stainless steel head from a forged billet. It comes with the Precision Milled TR Face technology and features a new variable depth face pattern that speeds up off center hits to supplement putting touch and reduce 3 putts. The Bergen model has a top sightline that extends to the back of the putter. Precision milling lines aid in alignment.