Bluetooth Headset Rotatable Stereo Earphone Noise Reduction Headphone Description: This Bluetooth headset offers you the wireless, comfortable wearing experience to easily control between voice calls and music with powerful and stereo sound. Features: [Fit for Right and Left Ear] 180°adjustable Ear-fit design allows you to adjust the angle to fit on your right or left ear. [Bluetooth 5.1 chip] It deliver efficient wireless performance for better connectivity and better sound quality. [Excellent standby time] 688h stanby time|48h call. [Caller ID Report] Announce caller's phone number, pause music for incoming calls. [Multipoint Technology] Supports two mobile phone the same. Never two phones'important call. Specification: Function Parameter: Bluetooth version: V5.1 + EDR Bluetooth mode: Hands free / headset power: 0.25MW-2.5MW Transmission range: 10meters Working voltage / current: 3.7V/ 8mA Battery capacity: 300 Charging voltage / current: 5V +0.25V/1A Charging time: about 1-2hours Standby time:688 hours Call duration:about 48 hours (for listening to songs, about 36 hours) Wireless frequency: 2. 402GHZ~ 2.480GHZ Support agreement: A2DP AVRCP HFP HSPTransmission Intelligent reminder: voice prompts/ call number broadcast Way for wearing: the style to hang behind ears and be into ears Battery type: 300mAh rechargeable lithium polymer battery Charging power supply: AC input 110-240V output 5V/1A Headphone net weight: 18g Headphone ear size: 7x4.4x2.2cm Package weight: 42g Packing size ：10x7.7x3cm Packing list: 1x Rear-mounted in-ear Bluetooth headset 1x Plug-in headset 2x Ear cap 1x USB charging cable 1x User Manual