US Patent 7351167 Baseball bat training aid and method of use

A training aid for a baseball bat includes an outer portion and an inner core portion which is relatively rigid with respect to the outer portion, the aid is for placement against a bat handle having an arched outer surface which is of a size to extend along inside middle knuckles of one's fingers for purposes of providing knuckle alignment while permitting a substantial portion of one's fingers free to grip the bat handle to provide a tactile sensation of gripping the bat principally with one's fingers and not one's palms and, which when so gripped by a batter, the training aid provides knuckle alignment for each hand and promotes anatomical superior fluidity of motion in one's hands, wrists and arms during a swing.