04621813 is referenced by 75 patents and cites 6 patents.

A correlated set of golf clubs the heads of which each contain (1) a sole including a trailing edge which is indented toward the striking face a distance of at least 1/16 of an inch, and (2) a lower back surface adjacent the indented trailing edge sloping upwardly and inwardly from the indented trailing edge toward the striking face. This configuration allows the club head material which would otherwise be located in the indented areas to be redistributed in the heel and toe portions of the club heads. The redistributed head materials increases the mass concentrations in the heel and toe areas which improves the resistance to twisting of the club heads upon off-center impacts with a golf ball.

Title
Golf club set
Application Number
6/660789
Publication Number
4621813
Application Date
October 15, 1984
Publication Date
November 11, 1986
Inventor
Karsten Solheim
501 Wakonda La., Phoenix, 85023
AZ, US
Agent
Herbert E Haynes Jr
IPC
A63B 53/04
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