Feature:1. [COMPACT SIZE] 8 channel relay module, which has compact structure, easy to install and does not take up space.2. [WITH OPTOCOUPLER] Onboard EL817 optocoupler, with optoelectronic isolation, strong interference resistance ability.3. [GOOD DURABILITY] Onboard 5V, 10A/250VAC, 10A/30VDC relay, with a long life and can be continuously pulled in 100000 times.4. [EASY CONNECTION] The relay module can be directly connected to the microcontroller I/O, and has output signal indication.5. [SAFE OPERATION] The relay control board has diode freewheeling protection for safe operation and short response time.Specification:Item Type: 8 Channel Relay ModuleMaterial: ResinWorking Voltage: 5VWorking Current: 10ASize: Approx. 79.5 x 71mm / 3.1 x 2.8in.Package List:1 x Relay ModuleNote:Pay attention to electricity safety when installing and using.