24" wheel (24" x 1.75" Tire). Rational designed according to somatology and movement features * Cotterless steel crank, Excellent manganese steel wheel bearing and frame * Extra Thick Alloy Aluminum Rim, Smooth riding wheel bearing, Large saddle in unique design for extra comfort & safety * Removable poly-nylon guarded rails on the seat, Quick release alloy aluminum lock for height adjustment * Full-sized nylon pedals with chromoly spindles, Excellent skid proof bulged-pattern on Outer Tire and butyl Leakage Protection Inner Tire