1 - Metal Halide bulb (See Option to Upgrade your Metal Halide and ballast to a higher Kelvin (Whiter & Bluer) and/or higher wattage (Brighter). For tank height 18" to 36" use MH 175W / 24" to 36" use MH 250W / 24" to 60" use MH 400W), 2 - 24" Super Actinic Blue 20W Standard Fluorescent Bulbs, 2 - 4" quiet fans, High Quality electro-white reflector, Black Alumnium canopy, Dimensions: L24"xW11.5"xH6.5"