ESP8266-DevKitC is a small-sized ESP8266-based development board produced by Espressif.
All of the I/O pins of the module are broken out to the female pin headers on both sides of the board for easy interfacing.
Developers can connect these pins to peripherals as needed.
The board supports various ESP8266 modules, including ESP-WROOM-02D and ESPWROOM-02U.