Wilderness Systems does not list hatch capacity anywhere on their website or product catalogs. The closest thing we could find was the dimensions of the hatch cover from their 2018 product catalog. That lists the stern hatch at 18.5" x 12.5" and the bow hatch at 10"x10". If you'd like more information you will have to reach out to Wilderness Systems directly, which you can do at 888-525-2925.
Hope this helps, thanks!
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