An apparatus for pumping and mixing plural components of differing viscosities having at least one hopper for accepting each component, each hopper having a hopper outlet; an auger secured within each hopper, the auger being designed to wipe the inside surface of its respective hopper during rotation; a piston pump plumbed to each hopper outlet, each piston pump being substantially identical and having a pump inlet and a pump outlet, and each piston pump designed to be joined by a coupling yoke, whereby components of differing viscosities can be pumped uniformly; and a static mixer. The static mixer has a mixer inlet and a mixer outlet, and is designed so that plural components of differing viscosities can be uniformly pumped and mixed.