There are a lot of articles and podcasts that tell you what you need for fly fishing. There is even content out there that details the backup gear you’ll need.
In this podcast, I talk about 5 (plus 3 more, at the end) non-fly fishing things you should have in your car if you’re going to be spending a good amount of time on the water. Sound abstract? Check it out, hear some of my horror stories, and think about if you’d be prepared in the same situation.
…and yes, duct tape is on the list.