Elfin Growth Hydroponic High PAR Enhanced Red and Orange Spectrums 400 Watt Flowering High Pressure Sodium HPS Grow Light Bulb Lamp Ultra Bright 51,000 Lumens High Pressure Sodium's Light Spectrum Stimulates Flower Growth and enhances Fruiting Expected Bulb Life: 24,000 Hours Improved Lamp Life and Lumen Output, 110V power voltage Startup Time: 10secs allow 3-5mins for full Warm up. Please wait at least 5mins after power shut off before striking again. HPS bulb compatible with electronic and magnetic ballasts (54,000 Lumens) Lifetime: 20,000 hours/ 2.3 years.