1, Supports Arduino Uno / Yun / Leonardo / Zero, the module gives your Arduino project the ability to control AC 115V/230V devices, easily makes normal home appliances become intelligent. 
2, 4 Channel solid state relays switch output. Rated output voltage: AC 100 ~ 240V(50/60Hz). Applicable load current: 0.1 ~ 2Amp(each channel). Solid state relays are different from traditional electromagnetic relays in that their switching life is much longer than that of electromagnetic relays. Note: the item can't support DC load.
3, One LED for power and four LEDs for relays status indicating. Relay control pin jumpers, allows to control the relays by custom pins other than the default pins. With a Reset button for Arduino.
4, Output terminal: Pluggable screw terminal blocks, top wire connect, pitch 5.08mm/0.2", strip length 7mm, screws - M2.5, steel, Cr3+ Zn plated. pin header and cage - brass. Wire range 28AWG ~ 12AWG / 2.5mm square.
5, Package included: 1x SSR Board (NOTE: the item not include Arduino module).