Rack pads from Mystic.. with a size to fit from a small car to a large Van. We have featured the 115cm set , as these are the widest rack pads we know of, so they are not 'widely' available. :) Mystic say.. 
If your car is already complete with a roof rack but needs a little extra cushioning to protect your boards, the Roofrack Pads are for you. This version features our Aero design, complete with shock absorbing padding, which fits most round roofracks. The expandable Velcro design ensures you can find the perfect fit. Available in a range of sizes to choose from, they come in a set of 2.