Will this Pro Canoe/ Kayak Carrier work for a 10ft kayak with the rear Expedition Rail kit installed on a Slimline II roof rack?

There a few variables at play. First, you the actual kayak brackets are adjustable- the closer you make them, the higher the kayak sits. Second, the size of your rack. If you have a large vehicle like a Sprinter van, then a kayak will fit within the expedition rails. Third, the curvature of your kayak- some curve up more than others at the ends. The expedition rail, inserted into the rear or side profiles add 3.5 inches of height. We recommend doing some measuring of where your kayak will be sitting on the rack and seeing which part of the kayak, if any, will be overhanging the rear rail, keeping the 3.5 inches of added height in mind.