Guys.....it is certainly possible that both results are individually accurate
I have never looked at a Huco catalogue, but suspect the AF sizing would be nominated as whole number & certainly not toleranced
Continuously cast brass or bronze sections are actually poured or cast through compressed carbon moulds which take into account the cooling & dimensional reduction that occurs
Typically for a hex section of less than 12.5mm AF, one could expect less than 120 m of product feed before the mould was considering to producing unacceptably oversized material
As an apprentice, I sent 6 months in the copper & brass foundry & one of my daily tasks was drilling out the blank carbon upper mould inserts with the nominated number & diameter of holes on the set PCD to ensure the correct molten fluid flow through the lower mould assemblies
For detailed measurement I don't use verniers with a TV set in the corner [but micrometers] , however vernier's with digital a image are far better for photography ....

afterall 0.443 x 25.4 = 11.2522....so the difference in component AF sizing is actually 0.0022 mm & that's a pretty small number ......

Derek