PlayWheels Dora Adjustable Quad Skate Size 10-13 Boot is made of Hi-impact resistant polymer plastic with "Auto-adjust" system that allows the skate to "grow" with the foot. The Chassis is impact resistant plastic polymer Wheels are PVC 54mm X 32 mm, bearings are 608zb speed bearings Dual toe brakes and safety straps Youth size 10-13 The boot easily adjusts to 4 different sizes with just the push of a button