I saw this thing at the last fly fishing show. I didn't buy it at that time but I received a coupon for a shop and picked it up. This thing is pretty neat and perfect for a canoe or kayak. The large roll is 10inches when rolled up and 16 inches when unrolled. I put it next to my wife's shoe so you can get an idea of the size.
This lower picture shows the roll all the way open. I added large flies so you could see how much space there was. The largest flies are 6inches or more. You can see there is plenty of room for other flies above or below them.
Another cool feature is the loop at the top that can be used to connect to a caribiner. The roll also comes with 4 velcro swatches.
These can be placed anywhere on a boat or kayak so you can easily access the roll and put it away. If you're wondering if the flies get smashed when the sushi roll is closed there is foam that lines the outter edge.
This creates just enough space so your fly material will not get smashed but gives the flies airflow so they can dry.
I'm really happy with the Sushi Roll so far. I like the portability of the unit as well as the amount of storage space. It has the same surface area as a large cliff box. I think the velcro part will be great for the kayak. I will be able to grab the flies and store them out of the way with ease. The product is a great value for $25.