The SMART HJC 21B is the 2nd Generation Standard Bluetooth Communication System model that supports 21B compatible HJC helmets, with structural interfaces that users can easily mount on HJC helmets. Based on the BT 5.1 low power system, the 21B offers Bluetooth 4-way intercom functionality, with over 22 hours of talk time. The enhanced sound provides users with an HD speaker, to enrich mid-to low-pitched sounds. Bluetooth 5.1 intercom up to 4 riders, universal connection with other brands Intercom range up to 1.6km (in ideal conditions) Audio multitasking with advanced noise control Voice Prompt HD Speakers Up to 13hrs of battery life Smart HJC mobile app required (available free on app store/Google play) APPLICABLE MODELS RPHA 2nd Gen Series: RPHA 71 / RPHA 72 / RPHA 91 / RPHA31 / RPHA 60 i71 i91 F71 The Smart HJC21B is equivalent to Sena model 10R
