* Fits 250W HQI lamp * Spring Loaded, German Made, Sold in pairs * Sockets made of corrosion/heat resistant resin, not plastic. * This holder is the "deluxe" version with spring-loaded mounting points for the double ended bulbs (both sockets are spring loaded). It difffers from the "basic" version in that the duel sockets are much thicker. Look closely at the picture above and you can see one of the spring loaded sockets. * Approx dimensions: 2" high, 7.25" long, 2" wide socket base with 1" rectangular sockets.. * Deluxe socket ends have approx 1.0" thick sockets, providing superior protection of your bulb ends. * Sockets are rated for 5KV pulse. * When mounting HQI-250 bulb into this socket, make sure not to touch the quartz sleeve with your bare hands. All fingerprints should be wiped off with a clean cloth soaked with alcohol. * Do not mount without a UV filtering glass shield!! This bulb will put out UV radiation which can damage your eyes and skin, as well as your animals in the tank. The bulb MUST BE burned behind a protective glass sheet.