Hortilux bulbs have long been considered the best horticultural bulbs on the market. The 1000 High Pressure Sodium bulb provides 25% more energy in Violet, Blue and Green spectrums than the standard 1000 watt HPS bulb. This optimization of spectral energy translates to promote vigorous plant growth. 145,000 initial lumens and a 24,000 hour life-span make this bulb the right choice for the serious grower or weekend hobbyist. This bulb can be used in both vertical and horizontal burning fixtures. Bulb must only be used in ballasts that can accommodate 1000 watt high pressure sodium bulbs.