HASA Folding Foldable Bike Shimano 18 Speed 20 Inch Size 12" 7005 Aircraft Alloy Frame 20" Alloy Wheels Shimano 18 Speed Shifter This model is one size fits all. Fit riders 4'8" to 6'3" in height. The seat post is whopping 550mm long to accomodate all sizes. We recommend that a rider's weight be under 240 lbs.