This handy add-on doubles your HoldUp 2 bike hitch carrier’s capacityfrom 2To 4 bikes – perfect for quadruplets on a family outing. Compatible withThe HoldUp 2 bike hitch carrier with 2" receiver only Add onTo HoldUp 2 bike rack, with 2" hitch
Strengths: Rock solid attachment to the Hold-up, easy & quick bike load/unloading.
Weaknesses: Heavy (40lbs)
Review bascially is the same as the one I did for the Yakima Hold up. This is the extension for 2 additional bikes. It's solidly built, and with the 2010 version it comes with a pin that adds stability at the hitch. It's easy to remove and store when you don't need to carry more than 2 bikes with the Hold Up.