These are suitable for use with any Class III/IV or Class V with a 2" receiver opening. We offer them in 3 bike and 4 bike models and in a variety of styles. Fold down models allow the rack to fold away from rear access doors found on vans and SUV's. Swing away racks, swing away from the vehicle access. Twister models are designed to accept a variety of tubular fraes found on todays high-tech mountain bike designs.