Progression of nmd Mice, an Animal Model of SMARD1

The apparatus includes an upper die, a replaceable first core member fixed to the cavity of the upper die by a screw, a titanium face plate for golf club head attached to the first core member and having notches and cuts for binding of molten alloy, a bottom die, and a second core member fixed to the cavity of the bottom die by a screw and having a projecting block raised from the top side corresponding to the sweat spot of the golf club head to be made for forming a hollow structure in the golf club head at the back of the sweat spot.