The Flowtron Replacement Lamp Ballast/Transformer is important for the UV Bulb and the zapping grid to keep working efficiently. The UV Bulb is the main method attraction and zapping grid is the only method of killing the insects. When the insects come near the bulb, the insects either get zapped and are killed instantly by the nearby non-clogging, high-efficiency shock grid. The Lamp Ballast/Transformer enables the Flowtron Bug Zapper series of products to work continuously to ensure you and your family are safe at all times.