You have a lot around lol. How many have you gone through?
Well it was the ones for the turbo to the intercooler. I had bought JBR's boost tubes & the dumb tube that goes to the turbo doesn't even fit, wound up coming apart instead. Plus his clamps are a 11mm nut so my low profile wrenches don't have a 11mm size for some reason.
Two of the spares can seal a 2.5" OD coupler. One is a t--bolt and the other is OEM worm gear. Both 10ish mm heads. I don't have an OEM K04 coupler handy to verify against. Verify sizing, cover local shipping, and they are yours.