Manufactured from optical grade, hydrolic 1 class borosilicate glass according to DIN ISO 8255 standard.Fully automatic production cycles ensure dust-free,absolutely clean cover glasses with excellent flatness and smooth surfaces.With their thickness varying 0,13 mm - 0,17 mm they guarantee perfect clearness.Their edges are cut with highest precision assuring flawless results. Alternative 2 glasses: economical quality cover glasses superior quality cover glasses