4 Amp Inductive load ( 13A resistive ) Plug and Grow -The original and Most reliable Brand all Hydroponic Plug in Timers on the market are a copy of this one Will switch 1 x 600w HPS /MH Ideal for LED Grow Lights plug and grow timer Heavy Duty Timer Grow Lighting is a problem for plug in timers -The Lighting load of Grow Lights are referred to as being an Inductive load -UK Domestic Plug in timers show their rating for inductive loads in brackets -so you will generally see this on the rating plate 13 (2) A - This timer has a 4A inductive load 13(4) A Will happily switch any standard grow light on the market