Product Name: Smart Hula Hoop Auto-Spinning Hip Hula Hoop Exercise Lose Weight Detachable Sports Circle Slimming Ring Fixed Hula Hoop Gender: Unisex Age: Suitable for All Ages Color: Grapefruit Powder, Charm Purple Material: ABS Kind: Hula Hoop Specification: 15 knots; 18 knots; 21 knots; 24 knots; Origin: China Product Description This fitness gear trims your waistline without torturing your hips. Instead of energy-eating manual spinning, this has a centrifugal ball that only requires a little force to get the same (or even more) results. And the best thing is this hula hoop can be strapped so you won't get bruised during workouts.