In a tennis racket having a racket frame composed of a fiber reinforced resin, the moment of inertia Ic of the tennis racket in a center direction thereof is set to not less than 13000 gcm.sup.2 nor more than 17000 gcm.sup.2, the moment of inertia Ig around a center of gravity thereof is set to not less than 80000 gcm.sup.2 nor more than 200000 gcm.sup.2, and the moments of inertia Ic and Ig are so set as to satisfy a relationship expressed by [30.times.(Ic)-(Ig)]/10000.gtoreq.31.

 
Web www.patentalert.com

> Method and apparatus for alarming decrease in tire air-pressure and threshold changing program

~ 00303