This is an excellent little digital timer.> Physical DesignThe unit has a simple, no-nonsense square design with rounded control buttons. The large main LCD display is not backlit, but is easy to read if there is enough light in the room. A recessed "Master Reset" button, and a red LED for relay enable, round out the face. The two outlets take up the bottom flanks of the unit, below the line of the controls.> ClockThe core clock is reasonably accurate - about as good as any quartz clock. My specific unit is accurate within a little better than one minute in one month.It can only display or operate in 24-hour time - there are no provisions for AM/PM display at all.The timer does NOT use the power line as a timebase, in order to easily facilitate the battery back up system. This reduces accuracy slightly.The label claims up to 120 days of reserve power. I have not tested this. However, all functions aside from actually energizing the outputs work perfectly fine when on battery, which makes sense.> Outputs/RelayThe main internal relay, according to the label, can handle almost all loads at up to the limit of a common outlet circuit at 125v15A, except for incandescent lamps - their very high inrush prompts a limit of only 10A, or 1250W.There are two grounded outlets, one on each side, making this little timer very versatile for finding ways to connect things.> Timing FeaturesThis is, of course, the headline feature of a timer.You have twenty available, independent start/stop programs, that can be mapped across different weekdays - every day, every weekday, both weekends, any individual day, all days except Sunday, Mon/Wed/Fri, Tue/Thur/Sat, Mon/Tue/Wed, or Thur/Fri/Sat.Different programs can overlap. The relay will follow whatever event last occurred.You can also override the programs by commanding the output to be either on or off until the next opposing command, or disable the program and force the output on or off.> How To UseI know that others have offered a "manual" for the timer here in the reviews, but just in case I end up near the top, here is my take on how to use your timer. I found it quite easy to use.>> Setting the ClockTo set the clock, press and hold the "Clock" button, then press "Week", "Hour", and "Minute" to advance each respective indication to the current day and time, and "Delete" to advance the seconds. Be advised, this unit does not have "hacking", so the clock keeps running the whole time you are setting it.>> Changing Time Modes, Temporary OverrideTo override the current output mode, press "Mode" to cycle through the following."ON AUTO" turns on the outputs until the next programmed turn-off."AUTO OFF" turns the outputs off until the next programmed turn-on.These also display to help you see at a glance whether the outputs are on or off on program, along with the relay light, and remain displayed and settable even in program mode."ON" or "OFF" without AUTO disables the timer features, and keeps the outputs either on or off.* If "ON" or "ON AUTO" is displayed, but the relay light is extinguished, your timer has no power. Check the outlet it's plugged into. If you're setting it while holding it in your hand, this is normal.>> Programming the TimerProgramming this thing is intuitive. I actually recommend unplugging it and holding it to set the program where you can easily manipulate the controls and see the display. Then plug it back in where you want it when done.Press 'Prog' to enter the programming menu.The small number on the left is the program number. Press "Prog" to cycle through all 20 programs.If the time says --:--, this event is available, otherwise it'll tell you what times this event is set for.The "On" and "Off" beside the program counter tells you whether you are setting the relay on time or the relay off time. These events are completely independent of each other, although the timer may act unpredictably if you set an "on" and "off" to happen at exactly the same time.Press the "Week" button to shift between the available day-of-week programs; every day, every weekday, both weekends, any individual day, all days except Sunday, Mon/Wed/Fri, Tue/Thur/Sat, Mon/Tue/Wed, or Thur/Fri/Sat.Press "Hour" and "Minute" to set the desired hour and minute for this event.Pressing "Delete" will erase this event. Be advised that deleting an "on" time does not automatically delete the corresponding "off" time, and vice versa.Press "Clock" by itself, or wait about fifteen seconds without pushing anything, to return to the clock screen.Pressing the recessed "R" button will erase everything, including the current time.LovePrint too smallThese work great, battery backup in the area I live is essential. Higher throughput than most similar timers. This is my third purchase of this product.I plugged my swamp cooler into this. So, it comes on automatically, but the best part is, I can go to bed and it will shut off automatically at 10 pm. BEST PRODUCT EVERGreat for indoor lights when growing seedlings. Not wanting to keep the grow lights on 24/7, I purchase these timers to help regulate the lights. Works well! Seedlings get 8 to 10 hours of spectrum light. Last year, I was able to plant seedlings that I grew indoors during the latter part of winter and transfer them to the garden so it gave me a head start. Honestly, the instructions are thorough however if you’re planning on setting this timer in five minutes you may get frustrated unless you’re super good with these kinds of hands-on gadgets. It took me 45-min. to learn how to program these timers and then program one to be consistent with the other since I have multiple lights. If you’re into manual programming and enjoy reading manuals, you’ll love these timers! My husband is usually really good with gadgets but he gave up on this because he said he couldn’t really read the grey numbers and words on the little screen, and there were too many instructions. My eyes are younger than his but I can see what he means. I’ve program these units a couple of times but do feel a bit of angst whenever I have to reprogram them.It works great and I like the two outlets it provides but is difficult to set up. I had to find a video on YouTube in order set it up.I'll have to say that this device is not the most simple to program.....and I'm not new to the digital world. However, once you spend a little time setting it up, you'll be happy you bought it. I got two in a bundle for just over $20 bucks. Now I need one with two plugs and two timers built in...I bought one on Amazon and find how much I appreciate this one. The new one is going to take hours to figure out. The one thing I didn't like about this was the 24hr time, but I can live with that. good product. Plus the price is easy to live with as well.It was a little bit tricky to set up, but it does its job really well and is super cheap. We had a power outage and the battery on board worked perfectly..For anyone who's having trouble programming it: Once you set the days, set the on time for example 6:00, then the off time 18:00 for 12 hrs. (6:00 am to 6:00pm)The tricky part is figuring out what is on and what is off. So, if it is say 7:00am and you want it to be on til the time you programmed (6:00pm in this example) Set it to AUTO ON. The red light will come on and if you plug your lights into it, they'll turn on. Say it's 5:00am, or outside the hrs you have set to have it on, choose AUTO OFF. If you do this, it'll automatically come on/off at the specified times. It's super frustrating at the start but that's the main thing that got it sorted for me. In the youtube videos i've found on this companies products they just set it to auto, not auto on or off, which isn't an option on this timer. You guys should probably change that, I've seen a lot of frustrated people.This was a total waste of my time. First problem is the printed instructions (which are absolutely crucial because this is a technical device requiring precise programming) or MICROSCOPIC (teeny print) and therefore illegible without a magnifying glass. This is so stupid I can't even describe it! Since the instructions are ESSENTIAL for the operation of this device, doesn't it make sense they should be PRINTED LARGER so they can be READ? Geesh. Secondly, the programming is NOT intuitive. Thirdly, the microscopic printed instructions are ambiguous and incomplete. Seriously, who wrote them? Make "English as a second language"? Dunno. And lastly, there is only an EMAIL ADDRESS for support questions. (No 'person' who can be called). Forget it. I have seen this scenario before with products manufactured in China that resold in the US/Canada. Total waste of time. It's going back to Amazon for refund.This timer has way more features than I actually need, and it does what I need very well. If you follow the instructions it will take you just a couple minutes to set up your timer. I am using it for plant lights so I only have one on and one off per day, but you can set a lot of them.I bought this over an analogue timer because I didn't want the constant ticking or buzzing. It is perfectly silent with just a single click when it turns on or off the power. Sort of like the sound of a light switch.Don't lose the instructions booklet... don't... There are seven modes to this thing, and the booklet is the only way to figure out how to get it working properly. I wish it was more straightforward to use this but... alas... very difficult.Functionality-wise, it works great when you program it properly. But this requires following the instruction booklet tediously (because of poor translation) and... Even if you know how to do it today, a few months later when you lose the booklet, this thing is probably turn into a dead weight.I have to admit, the self-included battery is very nice. You wouldn't lose the settings in the event of a blackout.It seems like a good product for the price. It's not doing exactly want I want it to do but close enough. I really need it to turn on and off electricity at specified times for an indefinite period but can't get it to do so. I am quite certain that this is a fault in the completely baffling instructions rather than a fault in the product itself. I am confident that the product can fully work. Right now I have various timer needs in my home but have to manually reset timer twice a day to do what I want it to do. That's ok and not a huge big deal but it does slightly negate the purpose of a timer.I have to wonder how hard can it be for non English speaking companies to provide instructions that can be understood by people in the country of sale. Surely all it takes is a bi-lingual copy writer as a one time job - can't be cost prohibitive really. Hell I'd do it myself if you can simply show me how all the functions work! I just received my 2nd one so clearly I like it and the price. Perfectly good product deserving of 5 stars but only got 4 due to lack of instructions. Maybe others will be more patient with that than me/or smarter/ or whatever!!!