So Greg, where are you going to mount a rod holder tube? The Yakima tracks?
These are water tight and have O rig seals. But check out the make your own kit!
http://www.hydroninc.com/pdfs/251_252.pdf
They are heavy duty, maybe too heavy duty. The end caps and brackets are aluminum and very strong. I have two short tubes tucked up under my van bolted to the frame that hold spare recovery equipment that I don't normally use, namely heavy duty chains and spare straps. I plan to put a 2nd set of tire chains in also. But I don't think there is any spot for a long tube that holds rods under the van
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