PURPOSE: To obtain predetermined engaging strength and simultaneously protect the edge of an engaging object by providing a male unit for engagement where an internal deep edge facing to inside of an engaging object of a ferromagnetic plate is bent toward the external side of fitting surface as an engaging segment and end point of such engaging segment is abutting or magnetically attracted to the plate through a hole.

CONSTITUTION: In a female unit (b) for engagement, a ferromagnetic plate 2 which is wider than a magnet 1 is magnetically attracted to the one pole surface of the square or rectangular magnet 1, it is fixed with a cover 3 consisting of non-magnetic material formed like a fallen saucer, a hole 3b for engagement is bored above the gap 3a and simultaneously position of the magnet 1 is restricted by a vertical edge collar 3c. In a male unit (a) to be removably attracted to such female unit (b), a ferromagnetic plate 6 is bent 6a in the direction opposing to the magnetically attracting surface and an engaging object (c) is fixed to this part. A punched engaging segment 6b is protruded so that it can eat adequately an engaging object (c). An internally deep edge of plate 6 is bent toward the internal side of fitting surface so that it is protruded from the plate 6, thereby forming an engaging protrusion 6c.