US Patent 7281989 Golf club head with gas cushion

A golf club head includes a body, a striking plate engaged with the body and including a front side for striking a golf ball, and at least one gas cushion mounted in the body and behind the striking plate. The gas cushion includes a bladder defining a gas chamber. The bladder is made of an elastomeric material. The gas chamber is filled with at least a gas to provide said at least one gas cushion with compressibility.