Use with Part A Epoxy Resin at a 4:1 ratio (4 parts resin to 1 part hardener). Features very low viscosity. Slow Hardener gel time: 35-45 minute at 72 deg F with set time of 4 hours at 77 deg F. Medium Hardener gel time: 20-25 minute gel time at 72 deg F with set time of 6 hours at 77 deg F. Fast Hardener gel time: 10-15 minute gel time at 72 deg F with set time of 4 hours at 77 deg F. Uses include hand layup laminating marine construction tooling epoxy face coats kit aircraft and vacuum bagging. Low odor and low to moderate toxicity.