Phone Skope's iPhone 7 Plus Case is one of two required pieces. This phone case is made specific to the iPhone 7 Plus and is made out of ABS plastic. Slide your phone into the case and then lock in the optic adapter (sold separately). This case will allow you to choose which of the two cameras you want to use at a given time. We strongly urge you to download the ProCamera app when digiscoping with the iPhone 7 Plus.