1. In a method of producing a sealed contact device which comprises stamping from a flat strip of magnetizable elastic material having opposite planar faces a substantially rectangular frame structure formed of a substantially U-shaped and a substantially T-shaped portion, said U-shaped portion including a short leg and a pair of opposite long legs connected to said short leg, one of said long legs being longer than the other, and said T-shaped portion including a trunk part connected to said longer long leg and extending substantially parallel to said short leg, said T-shaped portion being formed with an end portion spaced from the shorter long leg and extending in the same direction and laterally adjacent an end portion of the shorter long leg, bending one of said U-shaped and T-shaped portions back upon itself to a permanent position in which the end portion of said T-shaped portion and the end portion of said shorter long leg overlap one another in mutually spaced relationship and have mutually opposing contact surfaces, respectively, that are from the same planar face of the flat strip and form a normally open contact with each other, inserting part of the structure including the normally open contact into an elongated protective tube through an open end of the latter, so that the remainder of the structure including said short leg is located outside the open end of the tube, and sealing the open end of the tube.