Provide the best protection: The helmet consists of a solid ABS shell and a shock-absorbing EPS foam inner shell, and the accessories are made of soft and breathable foam. This combination lets children enjoy the experience of safety protection and effectively reduces accidental injuries caused by sports. Adjustable straps and knob: The children's helmets are equipped with adjustable straps and a dial for a better fit. The dial on the back of the helmet and the chin strap can be adjusted to your child's head circumference. Breathable material: This skater helmet has multiple vents and breathable foam. The helmets and padding help children feel cool and comfortable even during strenuous physical activity. Children's protective set with helmet: Our 7-in-1 protective set is equipped with 2 elbow pads, 2 wrist protectors, 2 knee pads, and 1 children's bicycle helmet. These children's protectors can be used as a special gift for many festivals. Size suggestions: 2 sizes to choose from. The "S" (48-54cm) is suitable for 2-8 years. The "M" (54-58cm) is suitable for 8-13 years. We sincerely recommend measuring your child's head circumference to choose the correct size.