... 2.eco-friendly 3.size: 20x20.1mm 4.DIN JIS copper sleeve Specifications:1) Suitable for various automotive, electronic, telecommunications, ... carbonadoing, others optional can be as requirements6)Material: iron/aluminum, copper, alloy, carbon steel, 18CrMnTi,20CrMnTi,20Cr,20CrV,1045 steel, ... will be protected strictly.4. Products could be finished per customer's samples or drawing 5. Could be packed ...