Powerstar are a reliable heavy duty contactor relay switch, available from The BigShop in four sizes.

*1Kw/ 1 Way*2Kw/ 2 Way*3Kw/ 4 Way*6Kw/ 8 Way

 A Contactor is activated by the timer and it routes the power to the light, bypassing the timer. Without one, timers will routinely melt or lose timer function (usually the light stays permanently on). They are essential for anyone using an HPS Growlight with a timer. Full 3 year warranty.