FWIW I've got a VO French headset sitting on my shelf and it doesn't have a split bearing seat since it's a caged ball version... I don't think they made a sealed version of the french headset. The race is stamped 26.4 in three places on the bottom. My only problem with it was that the stack height was a lot more than the original headset on the bike so it was useless. I don't know why they wouldn't choose to make it shorter since it's supposed to replace shorter steel headsets from BITD. Oh well!