The type DS sucker rod is manufactured from modified AISI A-4320-M nickel-chromium-molybdenum alloy steel. Our normalized and tempered heat treatment is specially selected to maximize impact properties while increasing fatigue life. Specifically formulated for deep, medium to heavily loaded, lightly corrosive, effectively inhibited wells. The DS rod is suited for reciprocating lift and PCP (progressing cavity pump) applications. All rods are shot peened per US Rod’s unique standards, improving corrosion and fatigue resistance. The DS is recommended for corrosive applications.