I work near Safeway, so I just buy grocery every few days and buy what i think will fit my panniers. If I have bulky items like toilet paper, I just use bungee cords and strap them to the top of the bike rack. Unless you buy stuff in bulk at Costco, I don't see what the use of buying special trailers. They are expensive too! Although, this looks really interesting...

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ID:	7680it's call bikehod Don't know how well it works. I've yet to see it in Vancouver