Believe both I.D. at 6mm plus or minus a few frog hairs.
Just mic'ed shaft diameters of barbed fittings of both fuel petcock and OEM carb inlet, did not mic the vent but believe all three require tubing that can be clamped onto our 6mm shafts equipped with barbs.
Didn't measure my non-stock tube O.D. but like a medium wall thickness, thin enough to bend , plus stretch over barb, yet thick enough not to kink and cut off flow in a tight radius.