A customer from one university of DE, who want buy the borosilicate sight glass for chemical experiment observation window. The size is 37.6*6mm, and the material is high borosilicate glass, it have a good chemical resistance. And it’s difficult to distinguish the high borosilicate glass, because there are so many craftsmanship of the glass. The borosilicate glass can resistant the acid strong sulfuric acid. Our company can make a custom, and use the best borosilicate glass, give you the top quality items.