Osram Plantastar 250w HPS(high pressure sodium) bulb has a very high PAR rating (the measurement of plant usable light) for an HPS light, in addition to having 30% more blue spectrum than a standard HPS bulb. It has an extremely constant luminous flux and a recommended lifespan of 12,000 burning-hours . After this time or every two years it is advisable to exchange the lamps as the luminosity drop to > 90%, so the light output decreases for your plants.
Being made by Osram these lamps are made to a solid, high impact construction, so are more durable than similar market competitor products.
It is a 220V bulb designed to be fitted with an E40 lamp holder.
Osram Plantastar 250w