Brand: HOCO Bluetooth Version: v5.3 Chipset: JL AC6973D4 Supported Protocols: Headset, Hands-free, A2DP, AVRCP Transmission Distance: 10 meters Transmission Frequency: 2.4GHz Speaker Unit: 13mm Impedance: 32Ω ± 15% Frequency Response: 20–20,000Hz Sensitivity: 98dB ± 3dB Battery Capacity: 320mAh (charging case), 40mAh (each earbud) Charging Case Input: DC 5V, Type-C Warranty: 6 months brand warranty