I remember that something on vaults is reverse threaded - can't remember if it's the end caps themselves, or one of the little nuts on the axle underneath - which is it? Want to do all mine, but trying to remember this before I start - already have a rounded end cap that needs replacing.
It's not the end caps (I wrecked some V12s with that confusion!) I think it's the axle nut on the right hand pedal because that's what miming pedalling with my hands suggests would cause a right hand thread to unscrew...
I think it's the nut on the axle too.
The end caps are standard but made of cheese so make sure you use a nice sharp allen key! One of the little nuts is reverse, but my brain can't work out which one it would be!
Cool, that's what I was leaning towards.
Been putting off trying to remove the rounded one, DMR sorted me out with a replacement axle cap FOC ages ago (nice folks), but it's seriously wedged in, a Dremel will be needed.
I got mine out by tapping it round with a centre punch - worked a treat.
The caps are soft alloy. Need a good quality allen key. Mashed up one and ended up cutting notches in it to get a flat blade in to undo. Then I got some spares. I also use copper grease on the cap threads for next time, and don't do them up stupidly tight.
The official service kit I think comes with replacement caps also. They get trashed by scrapes and rock strikes anyway.
Anyway, end caps are normal thread. Once off the nut under it will be the opposite to the thread on the other end of the axle, but remember the threading is different on each pedal.
If you read guides on pedal thread direction and which way to turn, be mindful that they usually show the pedal wrench direction viewing towards the bike, not from the hex socket side which can confuse you.
Or... easy way: tighten towards the front of the bike, loosen towards the rear. Works for both pedals, whatever way you look at them.