Filter Replacement - UV Lamp for (Year 2011 and Newer) UC150, UU250, UU350, & Any Reverse Osmosis with UV Item No. Included in This Set: UV-LAMP-4 Description: 4-pin (red and white cord) UV bacteria kill lamp Replacement Schedule: up to 1 year, not to exceed 1 year Filter Codes: 16 [note color=#f5f994]DO YOU NEED A 2-PIN UV OR 4-PIN UV? Take a look at your existing UV lamp's cord. Is it all white? Or is it white and red stripe? If it is all white, you need a 2-pin. If it's red and white like a candy cane, you need a 4-pin. If you need further help, don't hesitate to contact us. We're here to help![/note]