Metalwork 543211881300 'One' all in one air prep unit. This 1/2" BSP ported high quality Metalwork unit houses the below components - 

1. Filter
2. Condensate drain
3. Pressure regulator
4. Shut-off valve
5. Soft start valve
6. Pressure switch
7. Three supplementary air intakes

The entire user interface is at the front of the unit, making everything visible and easy to reach. All adjustments are made using the push-lock knobs.