The Ultra Sun 150 HPS Lamp has a Kelvin temperature rating of 2000°K which is ideal for the fruiting and flowering stages of plants. It can also be an excellent lamp for full term plant growth. These high pressure sodium lamps have been specifically engineered for horticulture applications. These Ultra Sun® lamps are of a very high quality, feature robust construction and have excellent reliability at an economical price. Do not handle with bare hands. If you need assistance in determining if this bulb is right for your set up give us a call and we will be happy to assist you!