Review on ⏳ DSmile Plastic Sand Timer - Set of 6 Colorful Sandglass Hourglass Sand Clock Timers - 30sec, 1min, 2mins, 3mins, 5mins, 10mins by Kelly Martinez

Of the four sets of six timers (24 pcs) I could only find a few semi-precise timers for 30 seconds, 1, 2, 3 minutes. By semi-accurate I mean timers that are accurate within 1% to 5% of the specified time. While this is reasonably acceptable in my opinion, the sequence is very unreliable and appears to depend on which side of the hourglass the time is being counted on. For example, while one of the 30-second timers is nearly accurate no matter which end the timer is started from, most others have a side that makes the elapsed time slightly over or well under 15% of the time listed. . I don't know how this happens because I think the number of grains of sand gives a very similar time no matter which side of the hourglass they move from. But I've found that the consistency of the hourglass shape can vary wildly, even when compared to the top and bottom of the same timer (see image). Also, NONE of my four 5 or 10 minute timers is better than maybe 35-40 seconds at best, and that only happens one of those two times and only maybe quarters of the time on just one side of them hourglass (see above), and only if the flow of sand does not come to a complete standstill due to blockage. I would say that on average you can expect to get a fairly accurate 30 second, 1 minute, 2 minute and 3 minute timer out of 24 quarters. -Package. At least that has been my experience so far.