Abstract: A fluid pump comprising a pump body and a roller holder having tapered rollers, the axes of which converge on an axis of rotation of the roller holder. A head case of the pump may be integrally formed with or support a pump tube or tubes. In any event, the lower half of the head case has a tapered surface which is complementary with respect to an envelope defined by an outer periphery of the tapered rollers. The head case is easily and removably attached to the pump body from the front side so that the head case with the pump tube or tubes can be simply and quickly replaced. Alignment between the pump body and the roller holder which supports the tapered rollers can be very accurately maintained to increase the reliability of the fluid pump by rotating the adjustable retainer.