MC 340-S1 is a universal magnetic contact set with NC function that can be used in both alarm and access control systems for monitoring e.g. doors and windows against unauthorized opening. This set includes MC 340 and the small plastic flange set MC 300-S1 for recessed mounting with screw connection in non-magnetic door and window frames. Both the contact and the magnet part are in a water proof (IP 67) plastic housing.