SFWS10 NB Stainless Steel Shaft:NB Linear Systems 25 1/2" Inch (647.7mm) Length 5/8" inch Diameter Shaft SFWS10 NB Stainless Steel Shaft, 5/8" Diameter x 25 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 both end threaded.