Official Bumper Case
Designed and sold by Google in the Play Store is the other options that is likely your best bet. The bumper case made by Google to perfectly fit your Nexus 5. It's a TPU case, and is extremely thin and lightweight, aligning perfectly with the camera hump on the back. Available from Google in Black, Red, Yellow, and Grey. This is my go-to case for the Nexus 5.
$34.99 on Google Play
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