Aluminium

3/2 Way = 3 ports for diverting flow. Typically used for spring return pneumatic actuated valves and air cylinders.

5/2 Single Acting= Power to coil Cylinder fully extends - power off cylinder fully retracts (or vice versa)

5/2 Double Acting= Power to coil one Cylinder fully extends, power to coil two the cylinder will fully retract, power off cylinder stays put.

5/3 Double Acting= Power to coil one Cylinder extends, power to coil two cylinder retracts, power off cylinder stays put even in mid-position.