I also have one of those outdoor timers with a cover, along with two or three of the normal hydrofarm ones,,, have never EVER had timer issues until I decided to try digital timers. I'll check back in with the digital timer scene in 5 years, they might have it figured out by then.
I did just pick this up though~~ Just an analog version of the digi one I have now,,, that's a POS.
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I have a couple of these,,, no problems. Can be wired for 120v or 240v which is nice.
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Hopefully before years end I'll be in a better place allowing me to comfortably run more wattage... Honestly, Id like to burn 20+ lights! Eh that may have to wait a few more years lol