It's really designed for a 430 watt magnetic HPS ballast...but, it works OK on a 400 watt HPS magnetic ballast.

430 watt ballasts are considered obsolete....but still work great!

Any 400 watt HPS Hortilux or Ushio bulb will do as well :thumbsup:
Dutch Pimp Reviewed by Dutch Pimp on . Son Argo 400 watt for all stages??? I am in the initial stages of planning a grow room. I am reading that the Son Argo 430 watt HPS has advanced tech that brings in higher "blues" than standard HPS bulbs which make it acceptable for all stages. Your feedback would be appreciated. Rating: 5