First let me say that I LOVE this Swiss watch. It looks fantastic and wears very comfortably. Below are few things you need to know BEFORE buying: 1. This is a MECHANICAL watch. The NH35A Japanese movement (ie, the mechanism inside that actually keeps time) is only accurate from about -20 to +40 seconds over a 24 hour period. You will not know what you will get until you test it on your wrist. Mine clocks in at -9 seconds/day (-4.6 minutes/month). However, it is still very precise (ie, the daily loss is almost exactly 9 seconds), so it is easy to compensate by adding 2 to 4 extra minutes at the beginning of the month, depending on how critical it is that you be on time. You will need to reset the date regardless after any month with less than 31 days. Importantly, this level of inaccuracy is EXPECTED for a budget mechanical watch per the specs above; mechanical will NEVER match the accuracy of quartz. If strict accuracy is important to you, use your iphone, or buy a quartz watch. Now that said, if you are intrigued by mechanical devices, and want to wear on your wrist a beautiful timepiece that houses the culmination of over a century of engineering and materials advances, including Nobel prize winning technology, that can (in my case) deliver 99.99% accuracy at 21,600 beats per hour (bph) using a miniscule hairspring, balance wheel, gears, and mainspring, that is wound by normal movement of your wrist, then this is the watch for you. More expensive watches have higher bph leading to smoother movement and somewhat better accuracy (+/- 10 sec/day, or even better for $$$$$) but may adversely impact longevity (ie, top sprinters may not be your best marathon runners). My watch started up shortly after placing it on my wrist and has never stopped (or been manually wound) since. It has a transparent back cover to allow you to view the semicircle winding weight, gears, and even the tiny hairspring/balance wheel that looks like a tiny heart beating as it oscillates. It can run 41 hours OFF the wrist when fully wound (power reserve). For what it is worth, the watch is imprinted with “24 jewels” on the back, whereas the Amazon description has “21 jewels”. The jewels are tiny rubies that provide low friction, resilient bearings for key moving parts (but otherwise have no value). More jewels is not necessarily an indication of a substantially better watch. 2. The warranty for this watch is essentially USELESS. After paying the 28 dollar appraisal fee, shipping, and insurance, you have paid most of the cost of a new watch (mine was $51 on sale at Amazon). Further, even after paying all of these costs, you may still be challenged by Invicta to prove that you did not void the warranty by opening the watch case, dropping the watch, etc. (see reviews on BBB and Consumer Affairs for proof of that). Bottom line, this is NOT a Rolex, and part of the reason you are able to get the watch so inexpensively is due to the inferior warranty. This is an $84 rendition of the Rolex Submariner that can cost up to $11,000 or more. Think of the 8928 as a disposable watch – so rather than getting all exercised and agitated if it malfunctions, or is damaged, lost, or stolen – just hop on Amazon and buy another one – remembering how many of these you can buy for the price of one $11,000 Submariner – plus you can wear it worry free whereas with the Submariner you would cringe and potentially suffer psychological damage at every bump, scratch, and drop. The above said, it is imperative that you fully test it during the 30 day Amazon return period. Wear it on your wrist as you ride your bike to expose it to handlebar vibration, gently rinse it off with cool tap water after going to the gym, and wear it as much as possible. Check accuracy. You have 30 days to complete your evaluation, and then you are at the point of no return! However, DO NOT drop it on any surface, or expose it to hot water, including hot shower water. These activities WILL ruin a mechanical watch—those activities are not testing, they’re destructive! 3. Being someone who has not worn a watch for over a decade, I had to look up what’s a screw down “crown”. The “crown” is the knurled set knob sticking out at the 3 o’clock position. Unscrew it counterclockwise until it pops out, gently pull out one click to set the date counter clockwise, and pull out a second click to set time (either direction). The second click also stops the seconds hand. Stopping the seconds hand ("hacking") right at the 12 o'clock position allows you to align the time exactly with your iphone. After hacking at 12, push the knob all the way back in when the seconds hand on your iphone sweeps 12 o'clock for the same minute setting. Just be sure NOT to attempt to set when the watch shows between 8 pm and 4 am (ie, when date is changing) to avoid damaging the date mechanism. I let mine run 12 hours after first starting it up to figure out if it was in AM or PM part of the date cycle before trying to set it. Also, if you unscrew the crown without pulling it out further, you can manually wind the watch clockwise (I have not had to do this). When done setting/winding, while pressing in, BE SURE TO SCREW CROWN BACK IN SNUGLY finger tight, or any exposure to water WILL ruin the watch. Do not set the watch when it is wet or excessively humid (eg, in the bathroom with steam from a hot shower). 4. Do NOT get this watch if you need to tell time in the dark. The “lume” (luminescence, or ability to glow in the dark) is marginally visible after exposing to good lighting, but only persists for an hour or so after lights are out. Invicta uses their “patented” Trinite technology for the lume – I would not worry too much about that IP being copied. 5. 8928 versus 8928OB: The only difference between these models in the gold bezel ring with numerals (20, 30, 40, etc.) that encircles the crystal watch face. The bezel is rotated to allow monitoring of elapsed time in minutes from a set point on the bezel. The 8928 bezel has a more attractive contour, but fingers can easily slip when attempting to rotate it. The 8929OB has an edge more like a coin, which is easier to turn, but perhaps less attractive. Be sure to look at photographs carefully before deciding. Both bezels have 120 "clicks" of rotation to allow accurate setting. 6. Although the 8928 is considered a “diver’s watch”, one rarely purchases this watch for actual use when diving. Rather, the watch is purchased by individuals who want a elegant watch of simple design that has very good water resistance (200 M) – and who may also want to monitor elapsed time in minutes using the bezel. 7. COLOR: The color is a VERY dark blue almost purple color; it contrasts well with the gold markings. In any case, bright light tends to brings out the blue color and makes it sparkle. 8. This watch is NOT for watch snobs, who will despise any product from Invicta. So, if you drive a Tesla, this watch is NOT for you. This watch is for those who know how to recognize value and accumulate wealth -- the Camry driver who invests the difference between his car and a Tesla into a rental property. If is a very attractive piece of functional jewelry for which you get a lot of bang for the buck.