Profile: Hasco Mfg. Co., Inc. specializes in manufacturing oil field equipment. Our product line includes twin pins, environmental safety seal liners, plunger rings, perforated nipples & gas anchors and hard faced metal plungers. We design and implement a color code system, which distinguishes different sizes and types of polished rods & polished rod liners. Our nipples and gas anchors deliver holes to permit free passage of fluid on the suction stroke and is used to eliminate hazards of slag. Our nickel pin plungers are used to protect against corrosion.