Abstract: Apparatus and system for making positive locking sealing rings having interengagable ring end notches with mating surfaces thereof at closely precise angles of intersection. In a preferred form, interal notch end faces, and ring terminal ends, are parallel and disposed at a slight angle to the ring axis to provide a positive angular interlock between the notches in a free hooked condition. The term "free hooked" as used herein means latched but not confined in a final assembly. The rings, including notches and ring terminal ends, are formed automatically in the apparatus of the invention by a unitized multiple component or faced cutter, such as a milling cutter. The cutting surfaces and cutter unit for the angled face notch design are advanced at an angle to the ring axis equal to the angles of the notch face surfaces.