. Insulated, rigid, Ø 4 mm, accepting spring-loaded Ø 4 mm plugs with rigid insulating sleeve. Brass sheet. The socket consists of two insulated, semi-circular contacts, which are connected to each other when a plug is inserted (switch function). The socket is screwed into pre-drilled panels of plastic, metal, etc. 2 × Flat connecting tab 4.8 mm × 0.8 mm.
