I assume the oversized 7x9mm oversized carbon rails means that they are ovalized and will not work with traditional seatpost clamps?
"NOTE: Oversized 7x9mm carbon rails are not compatible with seatposts equipped with side-load clamp mechanisms for 7mm round rails"
I have a Command Post Blacklite and Thompson seatpost as a backup.
Mtbr's 2016 Winter Biking GearReviews and Roundups
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