UCEC Calibration Weights for Digital Scale, 10mg - 100g Gram Weights Kit, Precision Stainless Steel Balance Scale Calibration Weight Set with Tweezers for Lab Educational Science

It has an extensive set of weights in a convenient (plastic) storage box. There are eight tiny square sheets that range from 10 mg to 500 mg, all with a raised end or corner to facilitate picking up with the included plastic tweezers. There are also eight solid weights: 1g up to 100g. I'm using it to calibrate my stylus force gauge, taking it on faith that the weights are accurate. At the price, it's not realistic to expect a precision set of weights, but perfection is the enemy of good enough.

I should preface this review by saying that I do not have access to a calibrated lab scale with mg accuracy, which is what I would use to determine the accuracy of these weights: use them with a scale of known accuracy with lab-quality calibration.HOWEVER...I got them to test the sensitivity and accuracy of a small consumer-grade electronic scale that I bought here, which claims to be sensitive down to the nearest milligram. For 30 bucks, this is quite a bold claim, given that the ones that you'd use in a proper lab cost thousands of dollars.But I got these weights and that scale at the same time, and then followed the procedure for calibrating that scale using the two 10g weights it came with.Now this set of weights comes with a set of 1gram and above weights, all of which my little scale came in within about 5mg of the nominal value.It was the set of under a gram weights that I was wondering the most about. This set has 500mg, 200mg,100mg...all the way down to 10mg. Rather than taking the familiar form of a small silver metal cylinder, these weights are smallish metal squares. Some reviewers complained that these squares arrive all bent up, but that's a feature, not a bug. The upturned corner makes it easy to grab with the tweezers even when the rest of the weight is flat on the surface of the scale. Which you definitely want to do, because if you even breathe hard on the smallest weight its liable to go flying off into the cat dimension, never to be seen again.Anyway, I was able to determine that my little scale does have milligram level sensitivity, however, the accuracy of it is probably +/- 5mg. Which is fine for my purposes, because for the stuff I am working with, I need to measure small amounts of stuff in the 250mg total weight range. So if what I can get is 250mg +/ 5mg--so long as the error is relatively small and more importantly, known accurately--one can usually work with that.If the level of your need for accuracy is truly down to the single milligram level, then you're going to want to pony up the money for a lab-grade set of calibration weights, and you're going to pay at least ten times the money that these weights cost.

I hesitate to review these weights after reading other ratings on both weights and scales. Obviously my level of OCD is not at the top levels acceptable to reloading!I'll start with the UCEC Calibration Weights for Digital Scale are not as nicely finished as my Lyman weight check set. But in function they perform well. The weights all come in with 0.005gr.of their rating. That is in comparison to my Lyman set on my Frankford Arsenal DS-750 Digital, RCBS ChargeMaster, and old faithful CH oil dampened beam scale, am I showing my age when I say I bought the CH beam new?? BTW: I do have a magnetically dampened RCBS beam and the CH oil deepened beam beats the RCBS hands down! I'm happy with the weights. I'll even use the questionable quote "for the money."😎You want more accurately, just pay for some laboratory calibrated weights, they will satisfy your OCD.,

Very convenient to have to check the accuracy of your scales. I used 3 different scales to check the accuracy of the weights. They're spot on

This is great for making sure your weight scales work correctly. Product is as described.

10g weight was off by 0.1g and the 100g weight is off by 60mg, definitely not withing the +-3mg spec. The plastic container smells worst than the plastic at harbor freight. Weight are kinda crusty too. The rest at least are within spec, but kinda hard to trust them considering 2 if the weights were off by so much. I weighed them using a miligram pocket scale and an analytical balance with 0.001g readability. Both were calibrated with their included cal weights and read within a few mg of each other. I didn't expect much based on the price, but 100mg off on a 10g weight is basically useless.

I have used the scale for about a week, and it is working just fine.I would recommend this scale.

Solid S.Steel and very small aluminum weights for the lowest size weights (goes down to 0.1g)Good value. I even dropped the case onto hardwood floor and it didn't bother it at all ! !