The Sun-Glo Fluorescent Aquarium Bulb is a linear fluorescent bulb with a color temperature of 4200 Kelvin and fits all suitable standard and electronic ballasts, Color temperature for fluorescent lights is assigned a value based on a human color perception that matches the color of the particular lamp, This Sun-Glo Fluorescent Aquarium Bulb generates a natural looking daylight spectrum with a refreshing natural white light for a balanced and natural look to any aquarium, but is most suited for freshwater communities, Glo T8 bulbs feature quality components and raw materials that contribute to a long lasting performance, Linear fluorescent T8 lighting technology offers excellent energy efficiency, The Sun-Glo Fluorescent Aquarium Bulb Features and Benefits:, - T8 25 mm diameter bulb fits standard and electric ballasts, - Energy efficient, - Close placement to water surface offers the potential to maximize light entry into the aquarium, - High CRI values for accurate viewing of aquarium, - Low heat production, - Generates a natural daylight looking atmosphere with the use of white light, - Perfect for all standard and electrical ballasts, 24" length SKU: RCHG0481