Evnroll Gravity GG4 Putter GripVirtually eliminates face rotation through impactInstant AccuracyThe number one goal in putting is to “hit your lines.” That means maintaining a square face angle to the target line before and after impact.Introducing a break-through in putter grip technology.The Gravity Grip has an ultra-light EVA foam body that only weighs 35 grams and a 70 gram 10” steel rod directly under the shaft. This downward gravitational pull of the steel rod tells your hands the position of the putter face. Tying the hands to the putter face promotes keeping the putter's face angle square thru the entire hitting area. This virtually eliminates face rotation at impact.GG4 - slightly over-sized rounded shape to quiet hand rotation