A golf club head comprises: a hollow main body made of at least one metal material and provided in at least one of a crown portion and a sole portion of the head with an opening; and an FRP part covering said opening and made of at least one resinous material reinforced with fibers, wherein the fibers...http://www.google.com.tw/patents/US7189165?utm_source=gb-gplus-share專利 US7189165 - Golf club head
