The DigiLamp 1,000W DE PRO+ HPS is among the highest rated lamp in the market. This commercial grade lamp packs 155K lumens with a nitrogen filled quartz arc tube. With a high PAR value of 2100 µmol/s, it’s designed for use in commercial greenhouse to yield high results and light intensity while still consuming the same amount of energy as traditional single ended lamps. The high PAR value provides an efficient photosynthesis reaction due to its increased omission of red and blue light. Light Retention – designed to hold 96% of its lumens and PAR after 1 year of usage.; Color temperature: 2,000K.; Operating position: Horizontal.; Average life hours: 20,000.