Net balls; Racket grip tapes; Rackets for tennis, racquetball and squash; Rackets; Sports training apparatus featuring a baseball bat, ball, and a tee for improving bat swings; Sports training apparatus featuring a rod with a target ball affixed to the end for improving bat swings; Tennis ball retrievers; Tennis ball serving machines; Tennis ball throwing apparatus; Tennis nets; Tennis racquets, baseball bats, cricket bats, golf clubs and hockey sticks; Vibration dampeners for tennis rackets