Twelve hours of playtime 3.5 hours is the battery charging time. Bluetooth version 4.1 15M is the Bluetooth® range. Wireless controls and a microphone 40mm is the driver size. Range of Frequencies: 20 Hz to 20 KHz With the acclaimed Positive Vibration 2 Wireless On-ear Bluetooth® headphones, you can experience freedom and get rid of all limitations. Our streamlined and environmentally friendly headphones, which are expertly designed with 40mm dynamic drivers, provide remarkable audio clarity and go well with almost any style. Positive Vibration 2 has large drivers, precise sound, and a 12-hour playback duration to keep you going all day.