The module has a DPDT 5v 1A relay. The module has a NPN transistor interface to control the coil. It also has a diode across the relay coil for protection. A high signal (5v-12v) energizes the coil and a low shuts it off. The relay has screw terminal connections of one set of Normally Open and Normally Closed contacts. A second set for the other contacts are pads on the board for direct soldering.

The user manual is below.