3840231 is referenced by 137 patents and cites 14 patents.

A collapsible and adjustable golf club characterized by the presence of a selector means that includes first and second interlocking systems having different spaces between their respective points of mechanical interlock whereby uniform increments of adjustment may be made to vary the loft of the club to a preselected angle and with the shaft of the club being collapsible for storage purposes.

Title
Golf club having adjustable head means
Application Number
05/329,096
Publication Number
3840231
Application Date
February 2, 1973
Publication Date
October 8, 1974
Inventor
Moore Donald D
Agent
Freeman & Taylor
IPC
A63b 53/06
A63B 59/00
A63B 53/02
A63B 53/06
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