Definitely this case: I have this version for my iPhone 5.
SPIGEN iPhone 5C Case Slim [Tough Armor] [Crimson Red] Air Cushioned Protective Case with Dual Layer for iPhone 5C - Crimson Red (SGP10545) http://amzn.com/B00EISGXSS
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I have the solid black one, this has to be one of the best iphone cases I have ever owned! Wife wanted one for one for herself after she seen mine, got her the silver and black so we can tell them apart.
I'm surprised to say it, but the Amazon Basics 5c case is really pretty nice. For $10, it beats a lot of more expensive cases, that's for sure. I'm using the white/grey one on my yellow 5c and it covers up most of the yellow (downside) that it doesn't really clash (upside). It's a pretty hefty case, though - with a silicone inner layer and a plastic shell on the outside - but it also feels very protective. It also has a really nice soft-touch feel to the plastic, so the silicone and hard plastic feel about the same.
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