Deluxe 4-Bike Hitch Mount Rack with 2-Inch Receiver, Bicycle Hitch Mount Carrier Car Truck Auto Racks SUV A21 4-bike rack fits vehicles with a 2-inch trailer hitch only . Vehicle will require professionally installed SUV A21 hitch to use this product. Heavy duty steel construction for durability, Quick attach bolt installs easily. Four plastic tightening knobs are aligned along with punched holes to lock bikes into a safe and snug hold. Carries: 3 to 4 Bicycles at a time, Capacity: 60KGS, Square tube size: 30x30mm, thickness3.0mm. Red Plastic Carrying Ball: 4 sets. Fits most cars, trucks, minivans and SUVs with either a 1-1/4" or 2" receiver. the bike rack has removable buckle straps, just attach to the upright bar of the rack, pull over bike arms and buckle for extra support.