16 Ago 5.500 (5-1/2 inch) x 3 inches, 4340 QT Alloy Steel Round Rod, HR
4340 HR Q&T (Quenched and Tempered) is prehardend to 35-40 Rockwell C hardness. 4340 HR Q&T is primarily used for heavily stressed parts that must operate under strenuous conditions. The Quenching increases the hardness of the steel, while the tempering makes it less brittle....