PURPOSE: To perfectly and surely holds a flyback transformer on a printed board assigned in an electronic equipment by holding a boss, projecting from the flyback transformer, with a flanged screw through a through hole provided on a cabinet.

CONSTITUTION: A flyback transformer 1 has a boss 4 formed integrally with a main body. A printed board 2 is assigned. A cabinet 3 is provide with a through hole 6 which is slightly larger than the boss 4 in diameter. In a state in which printed board 2 is built in the cabinet, the tip of the boss 4 is so assigned as it projects out of the cabinet through hole 6, then tightened with a flanged screw 5. With this, since the flyback transformer is held by screwing with a single screw, even at drop or vibration-shock applied, no large force is applied to the printed board, so cracking is prevented.