The Subaru Robin pump range includes a selection of centrifugal-clear water, diaphragm, high-pressure, semi-trash and trash types. The semi-trash models, the 2-inch PKX201ST and the 3-inch PKX301ST, are designed for handling water with small solids and light debris. Both pumps are powered by a Subaru Robin gas engine, rated respectively, at 4.5 and 6 horsepower. The 2-inch model has a delivery volume of 153 gpm, and that for the 3-inch model is 246 gallons. Both semi-trash pumps feature a hardened cast-iron volute and an abrasion-resistant, cast-iron, three-blade impeller.