VIVOSUN GrowHub Controller E42A, Smart Environmental WiFi Controller with Temperature, Humidity, VPD, Timer, Cycle, Schedule Controls, for Grow Tent Cooling Ventilation Lighting HOURGLASS Standard 2mm connector TENS electrodes EZYMATE Standard 2mm connector TENS electrodes pads are classic and commonly used in medical area this applicator allows for a clean the GrowHub Controller E42A monitors changes in both the internal and external environment Unify Your Equipment: You can operate them individually or unify all your smart devices through the GrowHub E42A platform to simplify the complexities of gardening to a scientifically manageable level and thus better stabilize your growth environment