27ghz sma to sma bulkhead adapters are in the sma 27ghz sma adapter section; the adapters below are all 18ghz. . Stainless steel sma adapters have their contacts gold plated per Mil-G-45204, 50 microinches; the brass sma bulkhead sma adapters are plated to IEC standards (commercial) and have 30 microinches of gold on their contacts. Also below are hermetic sma bulkhead adapters. These sma flange sma bulkhead adapters are useful when feeding signals through walls.