1. Pre-flashed with EZSP (EmberZNet Serial Protocol version 8)2. Can use ZHA Assistant or Zigbee2MQTT (pre-alpha)3. Base on EFR32MG21+CH340E4. +20dBm output gain,PCB antenna5. Plastic ShellSupport OTA Via Uart (Press the BOOT button,then press and release the nRST button, fiannaly release the BOOT button)Baud rate :115200It comes pre-flashed with an unsigned EmberZNet 6.7.9 Zigbee NCP application firmware with Silabs standard EZSP (EmberZNet Serial Protocol version 8) interface enabled as well as the standard Silabs Gecko Bootloader firmware for recovery, meaning it can be used either as-is out-of-the-box or flashed with custom application firmware via USB.Hardware is at its core based onSilicon Labs EFR32MG21 Series 2 Multiprotocol Wireless SoC(part numberEFR32MG2Different batches may result in differences in product appearance and color, which does not affect usageColour: parent-BlackMaterial:plasticPackage Contents:1 * ZigBee 3.0 USB DongleOnly 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.