The Ion 7.2 has high-end features for a great skating experience. The hybrid design allows the comfort of a soft boot with the support of strong ankle cuffs and stealthy aluminum frames. Grippy, bouncy indoor/outdoor Urethane wheels with speedy Silver-5 bearings ensure a smooth, quiet and confident ride. Designed to grow with your child, the Ion adjusts up to four full sizes at the push of a button. Size small adjusts from children's shoe size 11 to 1 and has 64 mm wheels. Size Medium adjusts from size 2 to 5 and has 72 mm wheels. ROLLER DERBY ION 7.2 Boy's Adjustable Inline Skates Feature: SIZING Adjustable sizing at the push of a button! Medium expands from size 2 to 5; Small expands from 11-1 BOOT Deluxe Comfort Liner, Locking Cam-Lever Buckle, Power Strap and speed laces BEARINGS Fast Silver-5 Speed Rated (carbon) Bearings FRAME Lightweight aluminum frames WHEELS Urethane wheels (Medium has 72 mm; Small has 64 mm) INCLUDES Tri Pack Protective Gear; Knee Pads, Elbow Pads, Wrist Guards Model # I145