Tempered Glass Materials Compared: Glass Types, Glue and Coatings — A Buyer's Guide Two screen protectors may appear identical in a listing photo, but in the hands of a customer, they might behave significantly differently. There are three unique materials: coating, adhesive, and glass materials. Whether you have a private label line or buy in bulk, the specification you choose influences your return rate, ratings, and how frequently clients return. This guide compares the options in the order they matter. 1. The glass: soda-lime vs aluminosilicate (high-alumina) Most tempered glass protectors start as one of these two substrates: Soda-lime glass [...]