Birch, Stewart, Kolasch & Birch, LLP
Golf club shaft
A shaft 6 has a forward flex of equal to or longer than 130 mm and equal to or shorter than 178 mm. When the forward flex is represented by f1, and a backward flex is represented by f2, f2/(f1+f2) is equal to or greater than 0.46 and equal to or less than 0.50. When a distance between a butt end Bt and a center of gravity Gs of the shaft is represented by L (centimeter), and a weight of the shaft is represented by Ws (kilogram), a butt end GLL is calculated by the following formula: butt end GLL=Ws×L×L,  wherein the butt end GLL (kg·cm2) is equal to or less than 110 kg·cm2. 
SUMITOMO RUBBER INDUSTRIES, LTD.
A A A A B B A A B B B A A A B B A
A63B A63B A63B A63B B29L B29K A63B A63B B29C B29K B29C A63B A63B A63B B29K B29C A63B
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Takashi Kenji
Nakano Takasu