This CRL 1/8" (D.S.) - 3/16" (5 mm) Corner Protectors is designed to protect glass and mirror edges during shipping, handling or storing. Black plastic Corner Protectors will not scratch or damage glass or mirror surfaces, and they help protect large cut-offs from breakage or becoming scrap. Protectors are reusable, they simply slide on and off the corners of glass and mirror. Ensure your customers are getting a quality piece of glass; protect the corners with CRL Corner Protectors.