rockbros kids bike helmet Size:S (48-53cm) *IP67 waterproof function

*IP67 waterproof function

- track the cadence and speed by earth induction

*Support ANT+ and Bluetooth connection

*GUB's new front and rear lights strengthen lighting and warning

rockbros kids bike helmet Size:S (48-53cm) *IP67 waterproof functionSize: Adjustable 48 53cm(S) 53 58cm(M) Weight: 365g (S) 390g (M) Material: PC Outer Shell, EPS Anti Shock Foam, Soft Liner inside for sweating absorb. Safety: CE Standard 12 Ventilation holes, Removable jaw parts Size: adjustable from 48 53cm(S) 53 58cm(M) Weight: 365g (S) 390g (M) Material: PC shell, EPS shock absorbing cushioning, inner padded sweat absorbing cushioning Certification: CE safety certification 12 ventilation holes, detachable jaw.