The iPhone 7 Plus has fantastic battery life. It’s easily among the best in the business when it comes to longevity, but there’s obviously always room for improvement. It’s also a pretty big phone though, so you don’t want to add too much bulk, even if it is in the name of extending your time between charges. The Sunwell iPhone 7 Plus Battery Case claims to be the thinnest 7 Plus battery case in the world. At the very least, it’s the thinnest case we’ve ever seen. It still manages to pack a 4,000 mAh battery that will more than double your iPhone’s battery life, and it costs less than $40 right now on Amazon.

Here are the highlights from the product listing:

  1. ## MAGNATIC SUCTION FUNCTION: SUNWELL iPhone 7 plus/6S plus/6 plus battery case can magnetic car mount holder, and also the battery case can standard himself to Liberate your hands when you watch movies.
  2. ## 1.2 TIMES BATTERY LIFE: SUNWELL iPhone 7 plus/6S plus/6 plus Case Battery with built-in lithium polymer , it can simultaneously for increased 17 hours Talk time, 12 hours internet, 12 hours web , 7 hours games. Super Ultra Slim Fashion design without excessive bulk.
  3. ## FOUR LIGHTS SHOW EXACTLY POWER LEFT: With the smart battery case on, when you click the bottom, there are 4 lights to show exactly how much charge you have left.
  4. ## SYNC TRANSFER: SUNWELL iPhone 7 plus/6S plus/6 plus battery case works with original APPLE light port , sync and transfer can be worked at the same time without moving battery case. It is compatible with all iOS versions including updates and Apple Pay etc.
  5. ## 90 DAYS FREE RETURN: If you are not satisfied with our iPhone 7 plus/6S plus/6 plus battery case or service, Please contact with us and you will be offered a full refund or replacement, Enjoy this absolutely RISK FREE purchase by clicking the yellow Add to Cart button.

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