Onboard mature and stable ESP32-WROOM-32E module, large capacity 4M BYTE FLASH The I/O port and UART program download port of the ESP32 module are all led out to facilitate secondary development Onboard AC-DC switching power supply module, power supply mode supports AC90-250V Onboard ESP32 module RST reset button and IO0 programmable button ESP32 supports the use of for ARDUINO IDE development tools, providing reference programs under for ARDUINO development environment Power supply port: 90-250V AC MCU: ESP32-WROOM (SMD) Material: PCB Color: blue Package Contents: 1 x Relay Module 2 x 10P Double-row Pins 1 x 6P Single-row Pin Only 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.