Archery shops have carbon fiber arrow shaft scraps that work perfectly for suspension toggles. They are very strong, incredibly light (lighter than aluminum ones), easy to drill for keeper string holes, and also easy to file smooth on the ends so they will not damage tarp or hammock. When I asked for them, the owner happily gave me a handful. Tested them this weekend on tarp and whoopie sling MSH, and they worked great.
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