I got caught out the other day when I punctured with insufficient sealant. I had a spare tube but I couldn’t remove the tubeless valve as I was unable to move the knurled retaining ring. I tried using a flat screwdriver tip from my multi-tool, but I just could not get that little bastard to budge. I ended up pushing for a few miles and using a pair of long nosed pliers once I was back home.
Can anyone recommend a small lightweight tool (maybe tiny pliers or similar) guaranteed to loosen off a very tight valve retaining ring?
Cheers, Tim

Leatherman squirt p4 is what I use.

You can get locknuts that are actually nuts, so you can use a small spanner. Failing that, its a standard thread so an appropriate nut can be used.