linear shaft: 1.shaft:SF5-SF80 2.Material:S45C or Gcr15 3.Precision:g6 4.Induction hard and chrome plated 5.Hardness:58-621. Optical axis is widely used in Industrial automatic machine,such as Industrial Robot,Automatic Recording instrument,Computer,Precision Printers and so on.Optical axis can also extend the uselife of industrial automatic machine. 2. We can offer linear shaft with diameter 5mm-150mm,maximum length up to 6000mm.When you have special requirements on length ,we can meet your machining requirements with different length. 3. When you have special requirements on machining,sush as threading,coaxial holes drilled and tapped,radial holes drilled and tapped,reduced shatf diameter etc.we can machining for you.And these special machining are after heat treatment and hard chromic so that ensure the precision of product. Please send us your detailed special requirement ,you should be satisfied with our service.