Watts WUVLAMP8, PWUVBULB8 UV Bulb 8GPM 30W, 24.5" Watts # 7100165, UV Bulb Lamp Effective Hours Rating: 10,000hrs - Ultraviolet Germicidal Light Bulb Base Type: 4pins ONE END Length: approx: 24.5" Bulb Type: T5 Style Quartz Glass Highest Quality Compatible Bulb at one Third of the Cost