I love this bag. I've had it…
I love this bag. I've had it for 10+ years. Very well made. 9"x18"x6" loaded and stores out of the way. It is very comfortable, provides plenty of cushioning for long paddles and holds a ton of gear stored out of the way. I have it pre-loaded with a large medical kit, rain suit, snakebite kit, folding saw, dry bag with a roll of paper towels, trowel w toilet paper, my canoe shoes and still room for more if needed. An 8"x17" cutting board acts as a bottom stiffener. There is a matching thwart bag available. I like it so much I bought a second one to leave in Florida with the canoe I keep there. I cannot recommend it more highly.
The Granite Gear Under Seat…
The Granite Gear Under Seat Bag provides a fairly large storage space within easy reach of the paddler. While not as easily accessible as a bow bag or thwart bag, the under seat bag is larger, with enough room for rain gear, lunch, and maybe even a light change of clothes. The rigid plastic interior bottom piece helps the bag keep its shape and maintain accessibility. It is well made of very durable 210 Denier Cordura, with good zippers and attachment straps and buckles. While it is not a purpose built dry bag, it does have a waterproof interior coating, and a flap over the zipper that will keep out any splashes, and the occasional light rain, as well. Also, given its location under the seat, it is inherently protected from the elements.