Sports Everlast Standard Duo Exercise Wheel

Two easy-glide wheels and molded handles provide an effective workout. Tone abs, arms, shoulders and back. Feel the burn as you roll in and out. Take this great workout tool anywhere It's portable and lightweight.
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Hand Sports Valeo Dual Ab Wheel

Got it at a great price. Nice burn from using it. I don't know that 2 wheels makes it better, but it does the job.
Only gripe was that it was almost impossible to put the foam handle on over the metal bar, that was a workout by itself, had to use all knowledge of physics and all brute strength in fingers to get job done.
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Ironman Double Ab Wheel

The Ironman Double Ab Wheel is designed to help its user tone and strengthen abdominal, arm and shoulder muscles

Valeo Dual Ab Wheel

Two non-skid wheels for stability and durability. Cushioned rubber foam grips for comfort. 1" spacer between wheels for added stability. Strengthen and tone abs, shoulders, arms and back.

Ironman Double Ab Wheel

The Ironman Double Ab Wheel is designed to help its user tone and strengthen abdominal, arm and shoulder muscles. Its rubber contoured handles provide a comfortable and secure grip and its double wheel provides added stability. The wheel is compact and portable.