The Ai-DUAL #7 DB Putter is a modern mallet engineered for stability and forgiveness. With a double-bend hosel and face-balanced design, it's perfect for straight-back, straight-through strokes. Add in the Ai-DUAL insert and FRD Groove, and you'll enjoy effortless roll and speed control, even on off-center hits. Odyssey's new line of Ai-DUAL putters feature their latest and greatest Ai-DUAL insert which delivers speed consistency across the face, incredible forward roll up and down the face, and amazing feel. Ai-DUAL Insert Designed using Artificial Intelligence, this dual-layer urethane insert has a soft outer layer and a firm inner layer delivering not only consistent ball speed across the face, but also enhanced forward roll up and down the face and amazing feel New FRD Groove This new Forward Roll Design Groove is deeper and more aggressive. With a 19deg slope it works in conjunction with the dual layer design to improve forward roll up and down the face SL 90 Shaft The standard length putters come with a lightweight steel shaft with 20-30 grams (depending on the grip) of counterbalance weight in the butt end. Odyssey's testing consistently shows that players strokes are more consistent with this configuration