The 5319 is a BNC Female to Phono Plug Adapter with Delrin dielectric. BNC is made of brass with nickel plated finish and gold-plated beryllium copper contact. Phono plug is made of brass with nickel plated finish and gold-plated brass contacts. It is featured with permits standard BNC cables (male ends) to be used with equipment having phono jacks. Gold plated center contact for minimum contact resistance and superior signal transfer.