OSP is the abbreviation for Natural and organic Solderability Preservatives, also called bare copper, Entek. To put it simply, OSP is really an natural and organic skin film that grows chemically with a clean up bare copper area. This movie is proof against oxidation, thermal shock and humidity and protects https://marcojsvxz.bleepblogs.com/31509191/copper-based-pcb-for-led-an-overview