1.stainless lead screw with brass nut 2.right hand with multi-starts 3.no treatment 4.very accurate stainless steel lead screw with brass nut What we can do: standard: DIN, BSW,ANSI/ASME,GB, etc. diameter: 3mm--80mm length: less than 5000mm screw pitch(lead): 0.5-24mm tolerance: +-0.01 material: carbon steel ,stainless steel and other available materials surface finish: zinc plated, nickel plated ...