The specific kit for the flushmount rails is the Kit4003 which includes the mounting adapter specifically for flush mount rails which goes into the footpack 460R which then attaches to the crossbars. Here is the link for the installation guide download to show how it works:
[URL=https://cdn1.static-tgdp.com/assetloader.axd?pimid=4003999&id=481561&brand=Thul e&market=US[/URL]
Here are some pictures of my wife's roof racks. These would be the same crossbars but different footpacks for mounting on the raised rails. These pictures give you an idea of how the crossbars will be raised and how long they are.
The aeroblade are more aerodynamic than most crossbars but still reduce mpg. I installed and was happy there was no whistling like I've experienced with other bars, but the truck went from 27mpg average to 24mpg average highway.
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2020 G01 X3 30e
CURRENT M Sport Package
2019 Ford Raptor SuperCrew
CURRENT 802A, KN Drop-in, RB Flaps, Husky Well Liners
2012 E70 X5M
SOLD Stg 1+ Turbos, DPs, Velos Stg 2+, JB4, Race Cats, Bavauto Coils
2003 E46 M3
SOLD aFe CAI, AP Axleback, SSK, H&R Springs, TMS CMBR Arms, PF RTABs