Parma is part of the opal glass collection by Bormioli Rocco. The chemical components used to produce opal glass give it a distinctive, unmatched white color. It"s made with a tempering process which provides significant heat and shock resistance so it will withstand breaking or rough surfaces and temperature variations. Opal glass is five-six times more resitant than normal glass and it withstands constant use so it will last longer. Opal glass is lightweight so it"s simple to handle and stackable, saving shelf space. In addition, it is non-porous and is a cleaner, more hygienic glass.