12 Volt relay interface board. Four (4) on-board relay modules. 

This can be controlled directly by a wide range of microcontrollers such as Arduino, Raspberry PI, AVR, PIC, ARM etc (because the microprocessor output only needs to drive the opto-coupler which is basically an enclosed LED)
Also very useful for other projects that require relay control, advantage being neat and easy connection to a relay or relays.
Opto isolated.

Relay connection via on-board terminal blocks.
On-board LED indicators.

 

Specifications:
Same relay specification on all relays: 
12v relay (requires a supply of between 8 and 12v), each requires approx. 25-30ma,
maximum relay switch:     30v DC or 250v AC (UK Mains)
maximum relay switch current:    10amp
Opto-isolator input:     between 1.5v and 12v
Module Size, approx. :    75mm by 56mm, height 20mm

Component board layout may vary very slightly from photo's
      Component board layout may vary very slightly from photo's