4 WHEEL ABDOMINAL BEARING SILENT ROLLER MUSCLE TRAINER Mo.FB049Quamtica four wheel abdominal Non slip Grip This grip adopts high quality sweat absorbent sponge, arc shaped thickened sponge, which lengthens the grip to be comfortable, non slip, sweat absorbent and wear resistant. Central Bearing Design Using high quality bearings, more flexible, but also exercise control. Using environmentally friendly ABS engineering plastics, no odor, healthier. More Stable This 4 wheel abdominal wheel is more stable. 8 back and