Rage Powersports BC4BM RV or Camper Trailer Bumper Bike Rack for 1-4 Bicycles Transports 1-4 bicycles on an RV or camper trailer bumper (max 140 lb. capacity) Designed for 4" to 4.5" square RV bumpers, installs with a 6.5" and 8" long bolts around the RV bumper 1.75"W Tire wells with 6.5" spacing between wells, 4.5" from bolt to first well Dual L-style support tie-down 19.5"H braces (bicycle tie-downs sold separately) Heavy duty steel construction with a black paint finish