Standard 2G11 - 4 straight pin base. UV Bulb 36W. Fits most UV units on the market. Includes Odyssea UV, Coralife Turbo Twist 12x, Tetra Pond UV3, HVAC and more. 2x UV Bulb 9 Watt 9W Germicidal G23 UVC Sterilizer Filter Odyssea Only.
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