Swagman RV Approved 4-Bike Bumper Rack Transports 1, 2, 3, or 4 bicycles on an RV or camper trailer bumper (max 30 lb. per bike) Designed for 4" to 4.5" square RV bumpers, installs with a 6.5" and 8" long bolts around the RV bumper Heavy duty steel construction with a black paint finish and powder-coated to resist corrosion Secure the steel U-Bolts provided with the rack to your bumper. The upright bar in the center of the rack gives added support to your bikes while towing Simple to use and supports various bike sizes, frames and wheels Transports 1 to 4 bicycles on an RV or camper trailer bumper (max 30 lb. per bike) Designed for 4&#034; to 4.5&#034; square RV bumpers, installs with a 6.5&#034; and 8&#034; long bolts around the RV bumper Heavy duty steel construction with a black paint finish and powder-coated to resist corrosion Secure the steel U-Bolts provided with the rack to your bumper. The upright bar in the center of the rack gives added support to your bikes while towing. Simple to use and supports various bike sizes, frames and wheels.