1. High-Performance 32-Bit Arm Processor, Fully Assembled And Tested, Supports , P-25, D-Star And System Integration2. Onboard Led Displays Status (Tx, Rx, Ptt, Mode) Rf Power Up To 10mw, Sma Antenna Connector, Including /Vhf Antenna, Can Be Installed Cleanly On All Current Raspberry Pis, Including Pi Zero3. The Firmware Is Preloaded And Can Be Easily Upgraded Via Software.4. 433 900 Mhz, Vhf 144 220 Mhz Opera Frequency5. Tx And Rx Have Different Frequencies And Support + And +Vhf Modes.Please select Modem: STM32_HS_GPIOSet TX frequency, RX FrequencyIt is best to Keep the TX and RX frequencies at least 10M apart.Function: SLOT1, SLOT2 supportNote:Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The UseColour:As ShownMaterial:PCB+MetalPackage Contents:1 x Expansion Board Module2 x Antenna2 x Pin HeaderOnly the above package content, other products are not included.Note: Light reflection 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.