Rumor: iPhone 7 to Feature Waterproof and Streamlined design
https://festwiz.blogspot.com/2015/12/rumor-iphone-7-to-feature-waterproof.html
One of the most defining features of the upcoming iPhone 7 is set to be its waterproofing. This has been 'confirmed' today by a new rumor out of China.
Also, both sizes of the iPhone 7 are expected to be waterproof. They will also apparently employ some "new compound materials" which will be used to hide their antennas and do away with those plastic stripes once and for all. This would let Apple streamline the iPhone design even more than before.

Catcher Technology will make around 30-35% of the iPhone 7 chassis and will remain the largest supplier of this component for Apple. The information above reportedly comes from a research firm analyzing Catcher's future sales.
However, this rumors are mostly based on speculations with no concrete evidence for now. Do however keep in mind that this is already the second rumor talking about waterproofing for the iPhone 7, so there may be some truth to that.
Source
Also, both sizes of the iPhone 7 are expected to be waterproof. They will also apparently employ some "new compound materials" which will be used to hide their antennas and do away with those plastic stripes once and for all. This would let Apple streamline the iPhone design even more than before.

Catcher Technology will make around 30-35% of the iPhone 7 chassis and will remain the largest supplier of this component for Apple. The information above reportedly comes from a research firm analyzing Catcher's future sales.
However, this rumors are mostly based on speculations with no concrete evidence for now. Do however keep in mind that this is already the second rumor talking about waterproofing for the iPhone 7, so there may be some truth to that.
Source