A peristaltic pump for pumping fluids through a flexible tube has a pump body, a support structure, a tube retaining mechanism and a linkage mechanism. Locating features make sure that the support structure is at a fixed location with respect to the pump body when the pump is in the closed position. The support structure controls movement of the retaining mechanism. The linkage mechanism applies the necessary force to move the support structure so that the pump is moved from an open position to a closed position.