☞ Hardened by quenching, Sturdiness and Durability: It is made of good materials, and the quenching process on the surface increases the hardness of the object. Not easy to deform even used long time, durable, accurate and stable.
☞Exquisite craftsmanship: Exquisite production craftsmanship, selected 40CrMnTi steel. Fine workmanship, Checked by multiple quality inspections
☞ Well polished: Smooth Inner hole, polished to shiny.