You are purchasing one Coralife 18 Watt UV Compatible Bulb for 6x, 77084, Turbotwist 18 W, 2G11 UV Lamp. Other Known Codes: Coralife Turbotwist, Tetra, Double Helix, OASE Bitron. Base: 2G11. The compact size of bulb allows for a small system design and design flexibility.
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