This board is a 2-channel relay control.
Each relay is switched by an optocoupler with an added driver.
Control with TTL level - suitable for nearly all microprocessors.
ON by LOW signal
Relay output is SPDT for each channel with max. 10 AMPs @ 125/250VAC or 28/30VDC.
Type of relay is SRD-05VDC-SL-CCurrenet consumtion by each channel 75 mA