SFWS6 NB Stainless Steel Shaft:NB Linear Systems 4 1/2" Inch (114.3mm) Length 3/8" inch Diameter Shaft SFWS6 NB Stainless Steel Shaft, 3/8" Diameter x 4 1/2" inch Long Shaft, the shaft is made of stainless steel, the shaft is 440C Stainless Steel, it is Case hardness is Rockwell 52-C56, the shaft is single end threaded.