Two bulbs for twice the reptile habitat convenience Thanks to this compact two-bulb housing, incandescent light and heat can fit in tight spaces. A low profile 4in high hood includes twin ceramic light sockets...perfect for daytime and nighttime bulbs. Both operate independently on separate cords with in-line rocker switches. An ideal match for day/night programming with an R-Zilla Power Controller (sold separately). For larger terrariums, place two of these 20in fixtures end to end.