... Information About the SpringMaterialStainless steel, carbon steel, spring steel, alloy spring steel, refractory steel, brass, bronze, etc ... Certification ISO9001:2008 ,ISO14001and ROHsEquipmentsAdvanced CNC computer spring machines with high precision and efficiencyTechnology Experienced engineers ,technicians ... 10 days for complicated samples which need mold open.4. For customers of first cooperation, ...