about Dinghai

Bimetallic barrel is 45 #, Common steel inner bore surface 40Ck 42GrMO and other light cast a layer of high wear resistance, high corrosion-resistant alloy layer, ordinary life than nitride, multiplied quenching barrel...

Shuangli Machinery

30 years focused on custom screw supplier

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Free hotline : 0580-8040046

  • SST700 series
  • SST600 series
  • SST500 series
  • SST400 materials
  • SST300 series
  • SST200 series
  • SST100 series
  • Quality is the market, improve to make progress
  • SBK7 Series
Special alloy steel cylinder Screw special alloy steel Accessory