This article is from the Sea Kayaking FAQ, by Todd Leigh with numerous contributions by others.
There are lots of different hatch designs out there. Considerations
when looking at hatches are watertightness, resistance to breakage,
and size. If you want to bring the kitchen sink, you'd better not just
have a 9 inch round hatch. Consider also that heavy seas and surf can
break or blow off hatch covers, so consider how they are attached to
avoid losing them, and don't depend on them for floatation of the
boat. If the compartments aren't full of gear, use float bags.
 
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