Mogoi Completely Soundproof V4.1 Bluetooth Wireless Foldable Hi-fi Stereo Headset Headphone Earphone for iPhone for Samsung

Specifications:
20Hz - 20kHz frequency response
64 ohms impedance
Passive noise reduction, Up to 15dB (blocks background sounds for an immersive listening experience.)
Battery: Li-poly 300mAh battery
Charging Time:2-3hs
Working Distance: 5~16metres