Excelvan 2 Packs BT 1.2KM/0.75MI Wireless Motorcycle Helmet Bluetooth 3.0 Intercom Headset Motorbike Interphone Connect Up to 6 Riders Warranty: 1 year with 100% satisfaction and zero hassle returns guaranteed. 6 Riders: Full duplex interphone supports 6 riders, a host and 5 auxiliaries. After pairing, the host can choose any one of the 5 to talk. Distance: Wireless Bluetooth intercom between separated riders is available at a distance about 1.2km/0.75mi. Usage time: Up to 8 hours talk time and 10 days stand-by time for a single charge. Universal protocol for cross-brand intercom compatibility. Noise control: Cut down background noise for both incoming and outgoing audio. Bluetooth 3.0 connectivity can listen to and share music, make phone calls with speed dialing and participate in a four-way intercom conversation.