Spectralux� High Pressure Sodium Single-Ended Lamps feature high lumen output and 2000� K color temperature, making them ideal for horticultural applications. Fruiting and flowering plants will thrive under these lamps! They can also be used as a full-term light source. They are engineered to be compatible with both magnetic and electronic ballasts. Spectralux� lamps are optimized for use with Sun System� brand ballasts and reflectors.