A2004 Aqua Ultraviolet Classic 40 Watt UV Bulb 33" 40W Gamma 40W Compatible Lamp Effective Hours Rating: 12,000hrs - Ultraviolet Germicidal Light Bulb Base Type: 4pins ONE END Length: approx: 33.18" Bulb Type: T5 Style Quartz Glass 100% Compatible with Aqua UltraViolet A20040