ASTM F1554 Grade 105 Threaded Rods are manufactured from medium carbon alloy steel that has been quenched and tempered (heat treated) to develop the desired mechanical values. This is the highest strength version of the F1554 Specification, with a minimum yield strength of 105 ksi, covering rods and anchor bolts in diameters ranging from 1/2″ through 3″. NOT WELDABLE