If the seller won't show you the light intensity at different points, they are hiding something.
Plants need much more "push." That same light might only effectively cover a 3'x3' area for bloom.
Look for Actual Power Draw . A high-quality 200W-300W LED is usually plenty for a standard 3'x3' tent.
The "engine" of your light determines how long it will last. Quality online brands will proudly list: Look for Samsung (LM301B or LM301H) or Osram.
Look for PPE (Photosynthetic Photon Efficacy) . A rating of 2.5 µmol/j or higher means the light is highly efficient at turning electricity into plant food. 3. Full Spectrum is King
They mimic natural sunlight, containing a mix of cool blue (for tight, bushy growth) and warm red (for big flowers).
Look for thick aluminum heat sinks rather than loud internal fans. Fewer moving parts mean a longer lifespan.