Lithium Ion batteries provide a consistent speed and torque from fillet to fillet, without reduced power or slow down as battery power wanes, producing 80 continuous minutes of runtime per battery without any loss of power. New Combo pack includes Cordless knife, 2 Lithium Ion batteries, 6″ & 7-1/2″ reciprocating style blades, wall charger, all packed into convenient EVA padded storage case. Comfortable, relaxed grip provides fatigue free filleting, while advanced air flow body design keeps engine running cool and smooth. Great anywhere you need a knife.