Headset size confusion

Could someone decipher this for me?

FSA NO.42/47/ACB w/4mm custom cone spacer

I need a new headset, so I think I'm looking for a 42 47 but are there any other magic things to sort? So many different codes!

Thanks, TIm


  • JBA
    JBA Posts: 2,852
    Look at page 103 in THIS DOCUMENT.
    “Life has been unfaithful
    And it all promised so so much”

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