a manually operated trigger sprayer is constructed with a reduced number of parts and in a novel manner in which all of the component parts of the sprayer are constructed of a plastic material . the construction of the trigger sprayer replaces the conventional metal coil spring in the pump chamber with a pair of plastic bowed springs that are integral with the piston rod and are positioned outside the pump chamber . constructing all of the sprayer parts of a plastic material enables a cost efficient recycling of the parts , which does not require disassembling the parts to remove a metal spring .