... 1.super light-weight 2.aluminum portable 3.nylon and air wheel for choice 4.folds easily for storage Aluminum super light ... ,high class nylon with ball bearing for smooth ground and air wheel for mud grasslandAluminum board edging,resisting the most rough conditionsDouble ... (kg)loading Q'ty (20'ft/40'ft)KB-511NAONylon Wheel, Aluminum Board, One DoorThree Colors to choose, Silver, Blue and ...