G/flex 650 Liquid Epoxy Resin and Hardener is a toughened, versatile epoxy for permanent waterproof bonding of fiberglass, ceramics, metals, plastics, damp and difficult-to-bond woods. G/flex is resilient enough to bond dissimilar materials and flexible enough to absorb the stress of expansion, contraction, shock and vibration. It is ideal for bonding dissimilar materials. It can be modified with WEST SYSTEM fillers and additives and used to wet-out fiberglass tapes and fabrics. Mixed at a 1:1 ratio, this 2-part epoxy gives you 46 minutes of pot life at 72F and an open (working) time of 60-75 minutes. It reaches an initial cure in 3 to 4 hrs and a workable cure in 7-10 hours.