04871168 is referenced by 10 patents and cites 7 patents.

A hollow plastic ball bat has an internally mounted swing metering device that provides a visual indication of swing velocity. The bat is defined by inner and outer members that are coupled to one another to define a recess that receives a transparent annular barrel. A bore in this barrel has a weighted piston that moves in the bore, as a result of its inertia, During a swinging or other movement of the bat itself.

Title
Ball bat
Application Number
7/260120
Publication Number
4871168
Application Date
October 20, 1988
Publication Date
October 3, 1989
Inventor
Jeffrey P Crouch
170 Brittany Farms Rd., New Britain, 06053
CT, US
Joseph A Autorino
170 Brittany Farms Rd., New Britain, 06053
CT, US
Agent
McCormick Paulding & Huber
IPC
A63B 69/40
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