This is a product from Navy Company. It has been used about twice. Retail price: 15,800 yen Completely dry backpack. Not a single drop of water will leak, so you can put it directly into your car. When going on an expedition, you can check it in on the airplane with all your gear inside. The length of the bag can be adjusted from 70cm to 130cm by tightening it. The shoulder straps have padding, so it won't hurt even when carrying heavy items. Navy Company Dry All Backpack Spearfishing Harpoon Fishing