This is a headset designed for long battery life. The L9 has a built-in 300mAh high-capacity battery for higher density, greater security and longer charging cycle. Built-in Bluetooth 4.1+EDR chip, strong performance, low power design, stronger signal. High-definition CVC noise reduction processing effectively filters out noise and makes people's voice clearer. Four colors are available for you to choose from, and there is always one that fits your needs. Specifications: specification: Type: ear-hook Communication: Wireless Agent: USB Wireless type: Bluetooth Vocal principle: dynamic Control button: yes Volume control: yes Active noise reduction: no Function: ordinary headphones, mobile phones, sports Plug type: wireless Sensitivity: 123 decibels Frequency response: 20-2000Hz Line length: 1.0 MT Resistance level: 9 Waterproof: No Model: L9 Support memory card: no Support APP: No Wireless: yes With microphone: yes Color: black, rose gold, gold, white Model: L9 Call time: about 36 hours Music time: about 32 hours Style: ear hook Connection method: wireless Type: Bluetooth Package Included: 1* headphone 1* pair of headphones 1* charging cable 2* ear hook 2* ear cap Notes: Note: **Size for manual measurement, a little error is normalthere may be 2-3 cm deviations **And due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you