The Yakima EXO DoubleUp EXO System Bike Mount attaches to either the EXO SwingBase or EXO TopShelf to allow you to carry up to two additional bikes. The Yakima EXO DoubleUp easily attaches using a cleat system for a secure and stable connection. With the StrongArm hook, you'll be able to secure your bikes at the wheels to protect paint and carbon frame bikes. Featuring this design, the Yakima EXO DoubleUp can be used on a wide range of different bike styles including women's specific bikes, kids' bikes, fat-tire bikes, and more.