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Smart HJC Sena 21B Bluetooth Communication System

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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
  • Advanced noise control
  • Intercom 1600mm
  • Voice prompt
  • Universal intercom
  • HD speakers
  • Audio multitasking
  • 4 way intercom
  • Includes BOTH mic sets: Boom-Type: Applicable for Modular & JET helmets and Wire Type: Applicable for Full Face helmets.

Designed to integrate with the following helmets:

  • HJC RPHA 31 Helmets
  • HJC RPHA 71 Helmets
  • HJC RPHA 91 Helmets
  • HJC i71 Helmets
  • HJC i91 Helmets
  • HJC F71 Helmets