Abstract: Medical personnel and lay persons are provided with a training aid to practice finding a cancerous lump in a human breast. A spherical ball is sized to simulate a cancerous lump. The ball is glued to the plunger of a microswitch. The microswitch is encased in a silicone insert which is molded inside a life like model of a human breast. When the ball is pushed down against the plunger, an alarm device such as light is activated.