S: Suitable for feet length 19-21cm. M: Suitable for foot length 21-24cm. L: Suitable for foot length 24-25.5cm. ADJUSTABLE INLINE SKATES - (Please must confirm the size before placing the order).Our inline skates have 3 different Unisex size , S/M/L, and each size is adjustable , . And do not forget to adjust the length of boot by the push button before wearing, you will find that it's so convenient to operate, and kids and youth can use it for many years even though their feet are growing up. 8 WHEELS ILLUMINATING - Our inline skates for kids come with 8 illuminating wheels that lights up automatically when you start to skate. The lights are powered by wheels rolling and never need replacement batteries! Just imagine how cool it will be to flash as bright as a lighting bolt in the dark! DURABLE AND SMOOTH - Frame of our inline skate is made from reinforced aluminium alloy , high rebounded 82A polyurethane wheels are wear resistant & more smooth, high-speed mute ABEC-7 bearings are made from premium quality carbon steel. Just enjoy a smooth, quiet and confident ride. FREE SKATES SOCKS & SINGLE BRAKE DESIGN - Unique fashion design skate socks will make your roller skating moment amazing. Reinforced heel and toe for resistance and outstanding durability. The single brake is equipped on right foot instead of two brakes installing on left and right feet to prevent the danger of falling backwards when braking.