Stohlquist’s Add-A-Buoy is a buoyancy bladder designed to fit the front pocket of a Personal Flotation Device (PFD), although it could also be inserted into an armor vest. The bladder increases the overall lift and face-up tendency of the vest it’s attached to, which is useful in big water rapids or stormy open waters. The buoy adds a maximum of 5 lbs. of buoyancy.
www.stohlquist.com/index.php?option=com_content&view=article&id=63
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