Kindly Reminder: This bluetooth module can only support Android mobile device.Used to communicating between the and Tool (mobile) over BLE. Note that the UART port on the must be enabled with a baud rate of 115200 for this to work. The UART port on can work only under 115200 baudOperating voltage: 2.0V ~ 12V Onboard Chip: NRF51822Actual use distance: The distance to communicate with is about 15 metersFrequency range: 2.4GHz2.4 GHz multiprotololl RF receiverARM Cortex-M0 32 bit processor256kB flash & 16kB RAMPCB size:27mm x 13mm2.0mm seven-pin four-wire connector length:90mmAntenna length:145mmnet weight:7gType: Suitable for V4Colour: BlackMaterial: composite materialPackage Contents:2 x Skateboard Bluetooth ModuleOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.