<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by rodster:
Check these out. I have two ($49 ea) and they're definitely Hummer grade.

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So these are the ones we were talking about a few days ago? I could definately see those with rubber matting glued to the side laying flat {or on edge if floor space is important to you) strapped down. Rubber matt preventing scratches to rack and slippage.
A couple of concerns.
1. Venting - I'm guessing they would be OK on a hot day on the roof with no vent?
2. Spillage with them on their sides - the caps would need to be really reliable, especially with the first concern.
hmmmm.