A bowling system for the visually impaired includes a handle slidable upon a rope suspended between two post set in shallow plates on the floor of a bowling alley between the ball return and foul line to guide the bowler to the foul line. A metal ring having a straight arm or rope with bells attached...http://www.google.fr/patents/US6599199?utm_source=gb-gplus-shareBrevet US6599199 - Bowling system for the visually impaired
