WeMos – Arduino Uno WiFi (ESP8266)

Specification:

• Microcontroller: ESP-8266EX
• Operating Voltage: 3.3V
• Digital I/O Pins: 11
• Analog Input Pins: 1
• Clock Speed: 80MHz/160MHz
• Flash: 4M bytes

Tutorial:

https://www.instructables.com/Arduino-WeMos-D1-WiFi-UNO-ESP-8266-IoT-IDE-Compati/