New Spirotech.

[picasso]

I think its to allow for fitting to existing installations, a bit like a pump valve where the nut drops down and there is a washer between the trap and the valve, I think

 

[SimonH2]

I see it has an arrow on it pointing up, can you change it if the flow is downwards?

it fits in pretty well any orientation of pipe. That knurled bit to the right of the arrow is a nut that holds the two halves together - with it slack, the two halves will swivel through 360˚. As long as it's possible to get that joint in a vertical plane (and have room for the filter) then you should be able to fit it.
The rear section is fitted on this pipework (above the orange bucket)

Untitled

• SimonH2
• 8 Jan 2012
• 1

Anyone have any idea what the additional fitting on the pipe below the filter is?

Looks like a small ball valve, and it looks like it's a separate part judging by the presence of the smooth stem disappearing into a standard compression nut on the main unit. The rest of the rear section looks the same as the earlier version. One pipe fitting is drilled a lot deeper than a normal compression fitting, so you can slide it onto one pipe and clear the cut end of the other pipe, line them up and slide it back - ie you can fit it where you can't push one or other of the pipes back.