*Disclaimer - Raw Wedges will rust*Milled Grind 4 utilizes laser etched Spin Tread and a raw face to provide better bite around the greens and superior spin in wet conditions. Refined shaping creates a smooth aesthetic that inspires creativity around the greens, while improved mass distribution provides a solid feel. Spin Tread technology utilizes laser etching to channel away moisture and help retain spin in wet conditions. The same way that tire treads help your car stay connected to the road, Spin Tread redirects water at impact and creates more friction between the club face and golf ball to impart more spin than prior generations.