Specifications:

Bases at CSR BC04 Bluetooth technology.
with build-in 2.4GHz PCB antenna
It’s at the Bluetooth class 2 power level.
Range test: 10 meters
Operating voltage: 3.3V to 6V DC
Operating current in pairing is in the range of 30~40mA.
Operating current in communication is 8mA.
Interface via UART, default baudrate at 9600 bps
Operating temperature range: -25 °C – +75°C
Dimensions 27mm×13mm×2.2mm