A series progressive divider valve comprises a valve body and pistons. The valve body comprises a fluid inlet, piston bores, outlet bores, porting and undercuts. The fluid inlet extends into an exterior of the valve body. The piston bores extend through the valve body from a first end to a second end. Each piston bores includes a piston. The outlet bores extend into the valve body, each outlet bores comprises a first set of outlet bores and a second set of outlet bores. The porting forms a plurality passageways connecting the piston bores to each other and with the outlet bores such that when high pressure fluid is applied to the inlet each of the pistons reciprocates from the first end to the second end in sequence. An undercut is located at an intersection between each passageway and piston bore.