Specifications: Bluetooth: Bluetooth V5.3 Operation frequency: 2.402-2.480GHz Supported profile: HFP, A2DP, AVRCP Operation range: UP to 10 meters Music time: About 25 hours (60% volume) Talking time: About 15hours (60% volume) Battery: 400mAh Lithium polymer Battery Charge time: 1.5~2 hours Operating temperature: -10~55? Speaker unit diameter: 40mm Rated impedance: 32Ω ± 15% Frequency Range: 20-20kHz Sensitivity: 119± 3dB Product size: 195 * 172 * 75 mm Product weight: 192g