Spectralux High Pressure Sodium Single Ended Lamps features high lumen output and 2000° Kelvin color temperature making them ideal for horticultural applications. Fruiting and flowering plants will thrive under these lamps! It can also be used as a full term light source. They are engineered to be compatible with both magnetic and electronic ballasts. Dimensions - 4.9 x 4.9 x 29.46 cm