1. USB-TTL converter.
2. Logic Level: 5V.
3. Operating Supply Voltage: 5V.
4. Digital I/O Pins: 14.
5. Analog I/O Pins: 6.

Uno WiFi R3 AtMega328p NodeMSU ESP8266 8mb Memory USB-TTL CH340G Compatible for Arduino UNO is full integration on one board: Uno R3 ATmega 328 and WiFi ESP8266 with memory 8Mb (MegaByte). All of the modules can work together or separately. And everyone has their own pinout headers.

The convenient solution for the development of new projects requiring Uno and Wi-Fi. Via USB you can update sketches and firmware for ATmega328  and for ESP8266 . For this onboard have the USB-serial converter CH340G.