Over at my site I've discussed fishing in depth often, frequently and constantly. I'm an expert fisherman and I can tell you one thing. If you don't have a fishing kit in your survival kit then you're not going to get food probably. I came to a decision early on in my survival kit building career and that decision was this.
"Wherever you are there are most likely going to be fish. All freshwater fish are edible and most seawater fish are edible. If I don't have anything to catch fish easily with then I probably won't be able to catch any."
I struggled as I built kit after kit and included what I felt to be not very concise or acceptable fishing kits. Doug's Kit includes a great and concise assortment, but his kit only makes up one of my two core kits. So I looked and looked and found this compliments of BePreparedToSurvive.com

here
I wrote a review of the
kit.I also invite you to read the dozen or so posts on my website about fishing in general. Many people have learned a lot from those posts and they're now first rate fishermen now.
EDIT: Yeah, I know what you are thinking. You could just copy the kit. If that's anyones intention the capsule is made by Nalgene/Fisher Scientific and sold on their site!