[rames14]

Per the directions, it is not supposed to rest on the roof. It is cantilevered over the roof. There are 4 Allen bolts that “clamp” the unit to the bed rails. I carry a 12’ Hobie Outback (82 lbs) plus (2) road bikes of about another 30 lbs. I use a Malone cradle on the back and a foam block on the front. The standard size is 5’, and I also went with the longer 6’ size. To put it on and take it off, I use a Harbor Freight electric hoist attached to my garage ceiling. Yes, you do get some wind noise, but not terrible. They do have a wind foil, but I haven’t tried it. The kayak loads from the back, which is why I selected the Pullrite 3900 to get to a clean bed. Be aware that US Rack does not come with bike rack attachment. I modified my existing Thule bars and rack to fit, so I didn’t need to invest for things I already had.