medical... the timers your talking about at home depot for under 10 bucks say 24 hr timer so wouldnt he still have to set it daily? im not trying to sound rude or stupid lol
24 hour timer just means you can make it go on and off at up to a 24 hour period. I just got a analog one cuz I'm cheap. The digital ones are about $15. It's a total pain in the ass to have to be at your grow room every 12 hours on the dot. Thank me later.
Works awesome, they are heavy duty, weather proof and simple to program. You can find them at most hardwear stores. If you are in Canada, Rona has them for $10.00 before taxes.
One thing to consider is if you have a lot of or regularily have power outages in your area, consider ones with better internal memory.
here's the timer i have. apparently has a whole bunch of settings (like you could have a different on/off time every day of the week) but it works just fine for going on and off at the same time every day