The Ultra Sun 1000W Metal Halide DE 10K Lamp emits a higher intensity blue and violet spectrums with an increase of the beneficial wave-lengths plants need! Mostly used during the last 1-2 weeks of growth, for final ripening at the end of the plants flowering stage. This lamp was designed specifically for high frequency DE Ballast, and the lamp construction on this bulb incorporates the electrical connection at both ends of the lamp, this removes the need for an inner frame. No frame, means no cast shadow from the beam! For Horizontal Operation Only The jacket of this lamp is made from quartz glass Oil from your hands can damage this lamp Must be used in an enclosed fixture with a protective lens Do Not Operate in an open style luminaire