I made this cover, to avoid small stone/debris getting inside the tyre that might cause a flat tyre. Correct airpressure is what I think causes most flat tyres, but this could be a soft spot too. Atleast on my m365, there is a lot of air between the rim and the tyre valve.
Printed in PLA, but TPU gonna be tested in the future.
If you need a nut, look for either a nut for schrader or dunlop valves ( both are same size).
If you cannot find a nut, try the ´"no.nut" file. It is a bit higher so the valvecap might push on it. Not tested at all, and I think it is only a last call solution, as the nut adds a better grib.