MBC Electric bell

Used to make experiments in Electromagnetism, model of an electric bell e. g.;
magnetic block "compact" (MBC) with ready-to-use electric bell (open coverage type),
sturdy plastic housing (ABS) with transparent base, printed circuit symbol (screen-printed),
jacks also suitable for 4 mm safety plugs, base with embedded neodymium magnets,
gong diameter = 60 mm
dimensions: approx. 84 x 84 x 39 mm