Glass Roller Bottles are used for the growth of mammalian cell cultures with Bellco Roller Apparatus. Specifications: Borosilicate Glass, Type 1,Class A 38 Mm Deep-Skirt, Nontoxic, Rubber Lined Phenolic Screw Cap Dimensions: 110x475mm Area (CM2): 670 Replacement Caps: 2029 Series Case Quantity: 2