It is an SLA-05VDC-SL-A 5Pin 30A Power Relay. The relay is switched with the help of a small signal from a microcontroller like an Arduino. This relay can be used to drive 30A devices.
Also check SLA-12VDC-SL-A 4Pin 30A Power Relay available on Robocraze. It operates at a voltage of 12VDC and has a load capacity of 30A at 250VAC or 30VDC.
I used the SLA Power Relay in a greenhouse automation system to control temperature, humidity, and ventilation. This helped improve plant growth and yield.