This water pump base replaces OE#: 43055A 4 and fits Mercury, Mariner, and Force outboard lower units with the following applications: 2 stroke inline 3 & 4 cylinder, metric 50-125hp 1987-current, and 4 stroke 50-150hp. This water pump base replaces OE#: 43055A 4 and fits Mercury, Mariner, and Force outboard lower units with the following applications: 2 stroke inline 3 & 4 cylinder, metric 50-125hp 1987-current, and 4 stroke 50-150hp.