Hi vint_mow and Paul
I have both a Kirby VK30 spec and a Kirby VK30 Operator manual.
Both say 1� pints.

The issue is, as said, did Kirby mean UK or USA pints.

[Linked Image]

Perhaps Gadge could help here.
In any case, 600ml would be a safe bet.

Cheers
---------------
Jack