The Grower’s Choice 4K 500W CMH is a single-ended ceramic metal halide lamp engineered to provide full-spectrum light that closely mimics natural daylight, making it ideal for all growth stages. Emitting a rich 4,200 K spectrum, it delivers an even blend of blue, green, red, far-red, and UV wavelengths that promote tighter internodal spacing, robust plant structure, and vibrant flower formation. With a high Color Rendering Index around 97‑98, this lamp ensures accurate color fidelity, enhancing both plant health assessment and photosynthetic efficiency. In terms of performance, the 4K 500W CMH outputs approximately 800 µmol/s of photosynthetically active radiation (PAR) and delivers close to 970 µmol/s in peak PPF, translating to around 115–120 lumens per watt. But if this lighting system is too powerful for your grow space, then take a look at the ROI-E420 system, or the smaller 10K 1000W SE for better light management.