Quality control is the biggest concern at Shower Door King. One of our team members unwraps each piece of shower glass for a thorough inspection.  We use a fluorescent light-box tower, in a dark part of our warehouse for inspection. This makes all tiny scratches, chips, and distortion stick out like a sore thumb. He then reject, polishes or certifies each lite of glass.
This attention to detail is one of the issues that separate us from every other shower door manufacture in the market.