SELECTED OPTION:TYPE: 4000MAH . Specification: - Color: Black - Battery Capacity of Charging Cabin: 2400mAh, 4000mAh - Headphones Battery Type: 3.7V, 50mAh Lithium-ion polymer battery - bluetooth: 5.0 - Support protocol: Support HFP 1.7, HSP 1.2, A2D9 1, AVRCP 1.6, SPP1.2, PBAP 1.0 - Call Time: 3-4hrs - Song Listening Time: 3-4hrs - Charging Time: 1h - IPX7 Waterproof Features: - With charging case 2400mAh, 4000mAh,can be used as power bank,can charge your mobile phone - Can automatically Pair, Power on after taking out from the charging case. - Wireless stereo, left and right channel seperation,both ear can be used seperately - Power capacity will show on your phone, you can see the power situation anytime, do not worry about the electricity ,make your life without worry; - Intelligent compatibility: support all bluetooth mobile phone, tablet, notebook, singing it, QQ music, movies, etc., universal all mobile phone Package Includes: 2 x Mini Headphones(Left One and Right One) 1 x Charging Case 1 x Charging Cable 3 Set Ear Caps(Small Size, Medium Size, Large Size) 1 x User Manual