I9 TWS Bluetooth Earphones

Bluetooth version: version 4.1 • transmission distance: outdoor distance of 10-15 meters • battery capacity: polymer lithium battery 55ma • listen to music time: 2.5 hours up and down / pause playback • talk time: 2 hours • standby time: 130 hours • charging time: 1-2 hours • operating current: 22ma • standby current: 4ua • -bluetooth class - bluetooth level: class2 and class3 • -frequency band band / band: 2.4-2.485ghz • -modulation process - modulation process: gfsk • -max. transmitter power - maximum transmit power: + 2dbm