In which case I can confirm that the 27.4 post is 27.4, and the 27.2 post is 27.2.
As far as you can measure the ID of a seat tube it appears to be mainly 27.0.
@Dammit started
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In which case I can confirm that the 27.4 post is 27.4, and the 27.2 post is 27.2.
As far as you can measure the ID of a seat tube it appears to be mainly 27.0.