Bike rack is a double layer roof rack that features a unique figure-7 shape, placing the vacuum cups in a perfect triangle for maximum holding capacity. It holds 1 bike (up to 20 kg). No e-bike. The Pro 1 double layer Polycarbonate deck has 3 TreeFrog vacuum cups, each rated to hold 110 kg, a fork mount and a strong ladder strap rear wheel holder. The 9-15 x 100 mm universal fork mount (sold separetely) securely holds either a standard 9 mm quick release or a 15 x 100 mm fork (with our Boost spacer works with 15 x 110 mm mountain-bike), no need to switch out fork mounts! Pro series are available with different 12 mm, 15 mm and 20 mm thru axle fork mount sizes (including Lefty fork) with no extra charge. It’s a great choice for any car, and it even fits in a backpack, so traveling with it is easy, and it’s an excellent choice for use with rental cars and can be mounted on the roof, hatchback, or rear window.