Your hammock maybe 10' 6" but when hanging, the distance from the ends will likely be 8.5' to 9' give or take so you'll have some coverage past the hammock on each end. Also, have you actually measured your hammock or are you going by the manufacturers specs? You'll find it maybe shorter than stated. That has happened with my ENO hammocks. ENO tarps are ok but do not offer decent side coverage IMO but if you can get an awesome deal, get the one that offers the most coverage.
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