The 250W Interlux Super HPS Bulb- high pressure sodium Super HPS-bulbs are tested and developed to work perfectly with electronic ballast, and are designed specifically for enhanced plant growth and flowering. The 250W Interlux Super HPS Bulb- high pressure sodium Super HPS-bulbs are tested and developed to work perfectly with electronic ballast, and are designed specifically for enhanced plant growth and flowering indoors. Featuring high Pressure Sodium that produces light spectrum shifted towards the red,It's ideally suited to use during the flowering stages of growth. Standard E39 Base. 1 year warranty.