Summary I changed my the design of the middle part of lens. It is more convenient . The wall thickness of the box there is 1.5 mm. If they were thicker - will increase printing. Use a rasp to expand the holes, if necessary. This back cover is not very convenient. If it will not fit to your phone - use the rubber band. I ordered a silicone suckers for the back cover. The phone will not slip. Watch for changes! https://www.youtube.com/watch?t=1&v=uzJ-a_K3tdc Print Settings Printer: Prusa i3Rafts: Doesn't MatterSupports: Doesn't MatterInfill: 0,15 Notes: Print all parts lasts about 5 hours. Use the glue to fix.