... tone up abdominal,back,shoulder,chest and arms muscles. Ab Wheel exerciser helps tone upper and lower abdominal muscles, obliques, ... chest, shoulders, triceps, lats, back and arms for an 8 in 1 workout. Small enough to go anywhere ... sure of the exercise you should do.Molded plastic discsDouble wheel for added stabilitySteel rod with comfortable gripsStrengthens arms, shoulders, abs ...