The ESP programmer is a breakout board to upload firmware on ESP8266 and ESP32. It benefits of USB-C connector, the new de-facto standard on the market.
It is equipped with CP2104 usb-serial converter and 1,27mm-pitched header to connect to ESP mcu.
It is designed to be attach to Lolin/Wemos D1 mini shield. If you are not going to used this form factor, you can break the external frame [video](...