Safety First! The helmets come in 2 different sizes and stylish colours that match the scooters. More than just a good-looking piece of head gear, there's an LED on the back for greater visibility, ideal for little ones who scoot home from school during those darker evenings as well as a comfy chin strap, so it doesn't dig in. Moreover, they are designed with 11 air circulation holes ensuring mosquitoes protection. They are, of course, tested in accordance with all safety standards. XXS-S size is suitable for 45-51cm head size.