Bluetooth version: BT V4.2 [downward compatible with 4.0, 3.0, 2.1, 2.0, 1.2, etc.] Bluetooth protocol: A2DP1.2, AVRCP1.5, HSP1.6 HSP1.1 (see comments) Talk time : 48 hours Music playback : 36 hours Standby time : 120 days Battery capacity : 280 mAh Charging time : 3 hours Charging Power : MICRO USB & Portable Power Headphone power: 32 ohms 5 mW Product weight: 12g Product size: 60.6*17.3*25mm Microphone: 4015/-38dB3 Speaker: 10mm in diameter Echo processing : CVC Headphone type : Ear-hook Multi-point connection: Support (one for two functions) Caller ID: Support Voice answering: Support There are 2 languages to switch Power display: Support (support IOS system power display, Androd 4.0 with plug-in display) TTS language: Chinese and English How to connect two phones: 1. Pair the first mobile phone with the Bluetooth headset first. a. In the off state, press and hold the multi-function button for 3 seconds. The indicator light will flash red and blue alternately. b. Turn on the Bluetooth function of the mobile phone, search for the Bluetooth device and find the corresponding Bluetooth headset to complete the pairing. 2. Pair the second mobile phone with the Bluetooth headset. c. Press and hold the headset multi-function button for 5 seconds to turn off the Bluetooth headset and keep the status of the first mobile phone unchanged. d. Press and hold the multi-function button again for 3 seconds, the indicator light flashes red and blue alternately, in the paired state. e. Open the second mobile phone Bluetooth function to search and complete the pairing 3. Connect the first mobile phone to the Bluetooth headset. f. At this point, the first mobile phone is disconnected from the Bluetooth headset. g. Keep the Bluetooth headset turned on, find the Bluetooth headset in the first mobile phone Bluetooth menu h. Connect directly (no pairing required). Complete dual connection, both phones can be answered by Bluetooth headset