OTA Programmer is a module which adopted the Bluetooth communication technology for transferring data between an ESC and a smart device (Android phone, tablet, and etc). It makes the wireless communication between ESC and smart devices possible; the user can easily program and upgrade ESC and monitor data transferring via this unit. Features / Why you need this? -HOBBYWING over-the-air firmware update. -Programming through a smartphone, smart devices -Access to HW Support* User Manual, Profile manager, etc -Fail-safe feature ( Disable a throttle control when OTA programming is enabled) *Recommend removing the unit before the official event.