... :lost wax process 3)satin or mirror polish stainless steel end capsSpecification1, investment casting ,precision casting2, carbon steel / alloy steel ... Lowest piece price ,higher tooling cost2) Loose inserts –Best for low volume parts3) Mutipiece wax Assemblies –Best for certain configurations , ... are listed from least to greatest cost1) Carbon and low Alloy steels 8620,4140,1020,1035,are best choices. ...