GOLF CLUB HEAD OR OTHER BALL STRIKING DEVICE HAVING FACE INSERT MATERIAL

摘要

A ball striking device, such as a golf club, includes a head with a face having a ball striking surface configured for striking a ball, a body connected to the face, and a filling material, which may be in the form of an insert, connected to a rear surface of the face. The filling material may fill in a thinned portion of the face, which may form a recess on the rear surface of the face that receives the filling material. The filling material has a density that is lower than the density of the face material. Depending on the size, shape, and location of the filling material, the weight distribution, the moment of inertia, and/or the center of gravity of the face may change.