3DR 915MHZ Radio Telemetry 100MW 100MW Wireless communication distance 800M Receiver sensitivity:-121 dBm Transmit power:20dBm (100mW) Transparent serial link Air data transfer rates up to 250kbps MAVLink protocol frame and status reports Frequency Hopping Spread Spectrum (FHSS) Adaptive time division multiplexing (TDM) Support and AFA Configurable duty cycle Built-in error correction code (up to 25percent can be corrected data bit errors) Use a small omni-directional antenna up to several kilometers Available bi-directional amplifier gain greater range Open Source Firmware AT commands to configure data transmission RT remotely configure data transmission Adaptive traffic control and use HM- wireless module based, with Si4432 Si1000 8051 microcontroller and wireless modules. Due to different product batches, the appearance , which does not affect use. Type:915mhz Colour:Black Material:Plastic Package Contents: 1 * Data Transmit Module Kit Only above package content, other products are not included. Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.