4 Epoxy 330 Tubes For Invisible Bonding Of Glass, China, Ceramics, Stones & Metals. This is a new set of 4 tubes of Epoxy 330. Used to bond gem materials to metal findings and takes a high polish for inlay. It can also be used for invisible bonding of glass, china, ceramics, stone, metals and other non-porous materials. Thickens in 15 minutes and hardens in 2 hours. Hardens in 10 minutes under a heat lamp. Each tube contains approximately 1/2 fl oz (14.7 ml).