Cardo Systems Scala Rider Q2 Multiset The MultiSet includes two ready-to-use SCALA RIDER Q2 wireless headsets for hands-free and safe bike-to-bike communication at distances of up to 540 yards as well as for use with mobile phones. General Talk time up to 8 hoursStandby time 10 daysWeight 1.18 oz 33.5 grBattery type rechargeable Li-PoCharging time 3 hoursRugged Design Rain and snow resistantCertificates FCC, IC,CE, BluetoothBluetooth version 2.0, class 1Bluetooth Profiles Headset, Handsfree monoChip manufacturer Cambridge Silicone Radio CSRIntercom Bike-to-Bike intercom communication up to 1,640 ft. 500 m range full duplex in wide open terrainRider-to-Passenger communications up to 33 ft. 10 m range with all scala-rider models full compatibilityAudio Noise cancellation MicrophoneAGC technology Automatic Volume Control according to speedVOX technology Accept or Reject calls by voice commandsSpeaker BoosterFunctional Fit to full and 34 HelmetsQuick-release mechanism for headsetTwo ultra-slim speakers 4.7 mm 0.18 in.4 large control buttonsHands-Free Profiles Voice dialLast-number redialCall rejectFM Radio 87.5 MHz to 108 MHz receiver6 Station memory with Search and Store functionsAutomatic radio muting incoming callsRadio On time typical 8-10 hoursCharger 110240V 5060Hz Universal Travel Charger