【Product specifications】Name: Integrated Bluetooth Modular Motorcycle HelmetMaterial: ABS shell + EPS buffer layer + 3D liningWeight: 1750 gSize reference: M (57 ~ 58 cm), L (59 ~ 60 cm), XL (61 ~ 62 cm),XXL (63 ~ 64 cm)Applicable gender: men and womenApplicable age: adultLining: Removable and comfortable liningSafety certification: DOT/ECE approved【Bluetooth specifications】Function: FM radio, stereo sound quality, answering calls, listening to music, listening to navigationBattery: 550 mA, standby 48 hours, 12 hours of battery lifeHost: waterproof, CSR 4.0 Bluetooth chipWith microphone: Built-in dual speaker headsetCharging method: USB charging (1 hours)【Package contains】1 * Bluetooth Motorcycle HelmetNote:The measurement of the helmet size is a manual measurement, there may be an error of 1 ~ 2 cm.If you are not completely satisfied with our products, please contact us, customer service will serve you within 24 hours!