I created the original version of this fuel pump for my 7mm/ft or 1/43 scale O gauge model railway. It's based on a type commonly seen in the UK I think probably from the 1970s to the present day.
A friend asked me if it would work scaled down to suit his OO gauge layout and this is the successful result.
There are 4 versions of the file. One without supports and two with supports which I have successfully printed on my Photon Mono X all inOO (4mm) scale.
I have also included a version reduced down to HO (3.5mm) scale, but I have not printed that version so I don't have a pre-supported version of the file in that scale.
As you can see, the photo of the printed model is a very cruel extreme close-up which shows that it still needs a little clean up where the supports were removed. At normal viewing distances I think it looks really good.
If you're looking for the O gauge/7mm scale version you can find it here:https://www.cgtrader.com/3d-print-models/hobby-diy/other/garage-fuel-pump-7mm-scale-o-gauge-model-railway