The Saris MHS allows you to create the perfect rack for your needs. It starts with three different base options, the 1+1, 2+1, and 3+1, letting you carry up to four bikes on the racks. The 1+1 allows for a single bike tray with an add-on tray. The 2+1 allows for two trays and an add tray or a cargo rack with an add-on tray. The 3+1 allows for three trays plus an add-on tray, or a cargo tray with a bike tray and an add on tray. All three versions are available for a 2″ hitch, while the 1+1 is the only version available in a 1.25″ hitch mount. The bike trays available are the Duo dual arm tray, the Uno single arm tray, and the 5.5 square foot cargo tray.