A definite step up from hardware store fixtures, these domes are specifically designed for the heating and light needs of reptile terrariums. Premium ceramic light sockets tolerate extreme temperatures from daylong operation of reptile heating bulbs. Solid aluminum reflectors keep their silver color over years of use. Each may simply be set on top of the terrarium's screen cover. Pair these products with an Zilla Power Controller (sold separately) for programmable on/off cycling.