Cat 290 Water Pump for Truckmounts AP44 3.5gpm 100-1200psi - 16.5mm Shaft - Dual End with Cover HydraMaster: Part# 111-044 - Aquacat, Bobcat, CDS 4.0, CDS 4.5, Hydracat 3.5, Hydracat 4.0 and Hydracat 4.5.