Thunderhead: 'a cumulonimbus cloud seen during thunderstorms.' Fishpond skipped Latin class - went fishing instead, as should you - but they gather it is a very tall, large cloud just itching to dump massive quantities of rain on your head. And gear ... they heard these things love soaking gear. Hence Fishpond developed a waterproof sling that would show contempt for these clouds with their fancy titles. It has spacious interior for everything you want dry, and a quick access exterior pocket with a water-resistant zipper. Add Hypalon tabs and D-rings for affixing tools, a slot down the back for your net, and a name that says "Come and get me you coo-moo-lowhatever!"