OP3 Smooth - OnePlus 3 Blank for case creation
This blank has the same dimensions as my OnePlus 3 phone.
I used this blank to make negative space within a cell phone case.
You could use a similar case like an IPhone 6 plus and shrink it a little and use this blank to create space for your phone.
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/6d2gz4MHrnc