You could get them fly fishing lures, if they fly fish, or the other kinds of lures.
You could get them "survival blankets"- the silver ones that are all folded up to tuck away in your camping gear.
Or maybe a book on these subjects. (local camp grounds or hiking trails or even maps)
Also, an "odd" tool like a "stubby" screwdriver or a pack of sanding paper.
Another idea would be wool socks- always good for guys who are outdoorsy types.
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If they are all into fishing and you are working on a tight budget, how about a few fishing lures to add to their own tackle boxes? I bet they would love that! I would pick out a few different types, depending if you know what types of lures they enjoy best and they can even trade with each other if some of your brothers favor a certain type over another.

If you stick to the fishing supplies, check out FishFreakOnline.com My brother has personally ordered from them before and he says their prices are great. They have a ton of lures to choose from, you even if you eventually find out, before Christmas of course, what types of lures they like best, I bet you that site will have them. You can easily spend roughly $5 per brother.

http://www.fishfreakonline.com/

Hope that helps! I’m sure whatever you decided on as gifts, each brother will love it!
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