... satin or mirror polish stainless steel flush elbowSpecification1, investment casting ,precision casting2, carbon steel / alloy steel /stainless steel3, SDM/OEM4, ... grind6, Heat treatmentHeat treat are used to control hardness ,mechanical properties ,corrosion resistance ,and surface treatment .unless otherwise indicated ... a normalize or anneal All 300 series stainless steel an 17-4PH are quoted with a ...