MAS Fast Epoxy Hardener is a non-blushing hardener with excellent moisture resistance that rapidly hardens at room temperature. The fast hardener can also be used as an accelerator for the MAS Slow or Medium Hardeners when customized cure times are required. Appropriate applications for this formula include bonding hardware, spot filling, and fairing. Additionally, the superior bonding strength of Fast formulas is ideal for high-strength secondary bonding applications such as structural tabbing and repair of laminations. The rapid cure time of Fast Hardener allows overnight curing, even in low temperature or high-humidity conditions. Allows a 2-hour working time at 70°F.