Why ZTR?

Real manufacturer factory, product quality controlled;
Independent R&D department, keep improving product quality;
Independent QC team standby, strictly testing;
Many years research and produce LCD screens

Before installation
Power off iPhone firstly. Keep iPhone off until all jobs done.
Make sure in a clean environment, no dust and static electricity.
Prepare all required tools.
Watch the direction video, if have no experience.

During installation
Disconnect the cable for battery firstly, when the iPhone opened.
Connected the cables in correct places. Test the screen after connecting all cables of the screen.
Screws have different size. All screws must be connected in original holes.

After installation
Test all functions of screen, display, touch response, 3D touch function.
Display issue like lines, spot are probably caused by static electricity. These issue could be resolved by clean the cables and charge iPhone.