Simple question regarding shank tail piece?

[TehCrucible]

Sorry this is a pretty dumb question but I want to get this right. Perlicks just rocked up (yay) and came with shanks and bits ect. Not quite sure how this bit is supposed to go together. Is the washer supposed to go inside the nut and before the tail piece or is the washer supposed to go between the tail piece and the shank.

Thanks in advance,
Jamie

 

[GalBrew]

The black washer goes in between the shank end and the tailpiece, the nut then clamps it all tight. It seals up the two bits so beer doesn't go everywhere.

 

[TehCrucible]

Perfect. Cheers mate.