1. Onboard mature and stable ESP-12F WIFI module, capacity 4M BYTE FLASH; The I/O port and UART program download port of the WIFI module are all led out to facilitate secondary development;2. Onboard AC-DC switching supply module, supply mode supports AC90-250V/DC7-30V/5v;3. Onboard WIFI module reset button; ESP-12F supports development tools such as ECLIPSE/ IDE;4. Onboard 4 5V relays, output switch signal, suitable for controlling the working voltage of AC/Load within 250V/Dc30V;5. Onboard indicator, 1 programmable LED and relay indicator.size:93 x 87mmMaterial:plasticcolour:greenPackage Contents:1 x Relay ModuleOnly the above package content, other products are not included.Note: Light 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. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-Minnanxin