The new TotalBoat 5:1 Epoxy pumps dispense, per pump stroke, 20 mL of 5:1 Epoxy Resin and 4 mL of 5:1 Hardener.
IMPORTANT: At the end of 2021, TotalBoat introduced new 5:1 Epoxy pumps. The new pumps do not dispense the same volume of resin and hardener as the previous pumps did. The new pumps also look different -- the resin pump has a white pump head, and the hardener pump has a white pump head with a black dot on it indicating the 5:1 mix ratio. Do not use the new pumps with the old Traditional 5:1 Epoxy pumps because they dispense different volumes of material. For accurate dispensing of resin and hardener, either use both of the new style 5:1 pumps, or both of the old style 5:1 epoxy pumps.