Osram Plantastar 400W is a high‑pressure sodium lamp for horticulture. The E40‑base bulb is rated 400 W and outputs about 56,500 lumens at 2000 K. It is designed to support photosynthesis in greenhouses and indoor gardens and is commonly used through both vegetative growth and flowering. Typical photon flux is around 725 µmol/s. The clear outer bulb measures roughly 285 × 47 mm and the product weight is about 150 g. Service life is rated up to 32,000 hours (B50), with high flux maintenance at 12,000 hours. With a suitable reflector, one lamp evenly covers approximately 1.0 m² of canopy. Operation requires a compatible HPS ballast/ignitor; nominal lamp voltage is 100 V with approximately 4.52 A operating current.
