Mizuno staff house...........scene of an epic BBQ on Monday night. Plus the table where Chris Wood and Bryson Dechambeau (not playing Mizuno clubs) faced off. Bryson did eat our burgers though.
Google Translate "Grain Flow Forged HD pursuing further hit feeling *
Mizuno's advanced patented forging technology, the world patent "Grain Flow Forged Manufacturing Process" evolved. Succeeded to densify the forging line inside the head to the ball striking part by a new manufacturing method. As a result, the ball hitting sound will sound longer and the hitting feeling improves.
The Boron was supposed to give it , the face, extra strength so that they could produce a thinner face and obtain faster ball speed whereas the HD looks as if it supposed to improve the feel and sound. The new 918 irons still have boron added.