It takes 4-pin n8117.1 phone, connection by screws. Valid mechanism for the series of Niessen: wave, Arch and Tacto
Mechanisms niessen 8117.1 Base socket for mounting on the Caps 8217.1
Universal box setup (search for reference vil544)
Connector RJ 11 with 4 contacts.
Valid for 2, 4 contacts jack
The series Arco NIESSEN is manufactured with insulation resin with high dielectric strength and excellent behaviour at high temperatures, metals stainless or electrochemical treatments that provide the greatest electric coonductividad, resistance to oxidation and deterioration due to external agents