FCO Ninebot BT2928 Engine Speaker bluetooth Subwoofer Type-C_x000D_ _x000D_ _x000D_ _x000D_ Main Features:â—Engine Sound Simulation System:can simulate the realistic engine roar according to the vehicle's accelerator, brake, speed and other signals.â—Suitable for Many Models of Ninebot: Through a special base, it can be easily installed on a variety of vehicles on the Ninebot.â—Standalone Bluetooth Speaker: 4x8W Ferroboron strong magnetism large-diameter loudspeaker, multi-directional sound field design.â—Metal Shell â—IP55 Dustproof and Waterproofâ—USB Type-C InterfaceSpecificationBrand: NinebotModel: BT2928 Protection Level: IP55Control Button Functions: power on/off, volume up, volume down, next song, mode switching.Charging Interface: USB Type-CSpeaker UnitSize: 50×50mmMaterial: NdFeBSpecification: 20 Core Dual MagneticPower: 8W×4Bluetooth SpecificationsBluetooth Protocol: HFPV1.6 HSPV1.2 A2DPV1.2 AVRCPV1.4 DIV1.3Bluetooth Version: 4.2 and aboveFrequency: 2.4GHz-2.48GHzWorking Distance: about 10mAudio SpecificationsNumber of Channels: Two ChannelsFrequency Range: 100Hz~20KHSignal to NoiseRatio: 80dB (2W)Battery SpecificationsRated Capacity: 2200mAh (7.4V)Play Time: 2~3h Charging Voltage: 5V3ACharging Time: 2.5hAmbient TemperatureStorage Environment: -10~60°CUse Environment: -10-50°CDimensionProduct Weight: about 0.72kg Package Weight: 0.99kg Product Size (L x W x H): 24.80 x 8.30 x 7.70 cmPackage Contents1 x Speaker, 1 x Type-C Power Cord, 1 x_x000D_ _x000D_