This is the FILA WIZY ALU model. It's for children and the size is adjustable. This model seems to come in three sizes: M, L, and XL. This one is L: 21.5-24cm. The size can be adjusted with the lever on the heel. The frame to which the wheels are attached is made of aluminum, which provides rigidity and makes for smooth gliding, and the wheel bearings are ABEC 5 for smooth rolling. I like these myself, so I was particular about buying them for my child, but they've only been used a few times. I hope someone else can use them. If you'd like, I'll also include the protectors. (The protectors show some signs of use.) - Brand: FILA - Size: L: 21.5-24cm Adjustable - Color: Black/Green - Model: Inline Skates WIZY ALU - Brakes: Yes