High-quality Speakers: BH51M NSO is the only helmet with sound by J-B-L that delivers better sound quality for music and phone call. NSO utilizes open ear speakers so you can enjoy music while maintaining situational awareness. The size of speakers increased by 57%, the sensitivity increased by 5dB, and the resonance frequency decreased by 180Hz. The sound quality of the bass is rich and full and the mid-treble is clear.

Smart Lighting: Using inductive LED lighting that activates automatically when dark. The smart lighting on the back of the helmet consists of LED bulbs that save energy and create stunning linear patterns when used to indicate the direction of the biker, which is controlled through the remote control.

Focusing on Your Safety: As the first brand to actualize patented Fall Detection & SOS Alert function in outdoor sports, NSO has special sensors that can detect your fall when an accident happens. An SMS alert will be sent to your preset emergency contacts with GPS location after 90 seconds.

Auto Power Off: LIVALL BH51M NSO smart helmet will be turn off automatically when the helmet is disconnected with phone and keep quiescence for 15 minutes.The helmet will automatically turn on when it moves.

Fits For Your Head: Medium: 21.65-23.23 inch / 55-59 cm; Large: 22.83-24 inch / 58-61cm