The ABS Company Ab Coaster PS500The AbCoaster PS500 puts you on the fast track to great abs! This machine works exactly the opposite from a traditional ab crunch machine. Rather than working your ab muscles from the top down, the Ab Coaster PS500 works from the bottom up, helping you target those hard to reach lower abs. Just kneel on the comfortable carriage, and pull your knees up. Its as simple as that! As you lift, the knee carriage glides along the biometrically designed curved