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Input:
Question: Have you been able to calibrate this? I've followed the instructions but get "ERR" after 20g. Uncalibrated it is off by 0.018g
Document: These are included, but you need to remove the protective flap in the battery compartment before you can start using the scale.The scale is accurate to within 1 mg (0.001 g). In order to get this level of accuracy, though, you might need to properly calibrate the scale. I have discovered that the scale is very sensitive to the precise orientation on the table or desk on which it's placed.
4 stars because it &#34;jumps&#34; when adding weight.I bought this for reloading ammunition. I was sold because of another review stating the specification in the manual (which really should be in the description) that it reads in .02 grain increments. It reads well and I am able to get my loads within a tolerance I am comfortable with.I would rate 5 stars if the scale read at a quicker rate.
There are also four little non-slip feet.The display is surprisingly easy to read and the buttons are easy to operate. It is a simple matter to calibrate, tare, or to change units and there is even an add-up feature for calculating the total weight of multiple objects.Two 10 g calibration weights are included as well as a pair of fine-pointed tweezers for handling diamond melee or other tiny objects. There is a small pamphlet with complete and literate instructions.
Ok scale for the price although it's not reliable under 99mg it has a error amount of about 20mg even above the .099 decent to the second decimal though. Not good enough for measuring medication or chemicals which is what I wanted it for. I have a better 0.01 scale for same price. I really need the third point so I am disappointed. Will not recommend. Jumps around too much,  must calibrate each time and after it is still wrong by at least 20mg.
This has a pleasant blue back light which allows the LCD display to be read in the dark or in a bright sunlit area. The scales weigh up to 20g in 0.001g increments and can also weigh dwt, ct and gn, though I can't profess to ever having needed to use some of those modes.I would normally drop test items and throw them around a bit to demonstrate robustness, but as these are so delicate I have no doubt that it would cause damage as would any precision instrument.
Unless you are going to spend significantly more money on a scale, this is about as good as it gets at this price range. Great for measuring jewelry, powders, or just about anything else between 2mg and 20g.
Would of been very pleased if not for the fact that it had no instructions with. Otherwise item it self was excellent if I understood more about it would have been pleased.
This is a perfect scale for me. Nice size, accurate and compact. Comes with the weights to calibrate which is nice.
Works great for weighing coins and other small objects, easy to set up and calibrate with the provided calibration weights.
I had initially received a scale that was broken but MeasuRite was very kind and easy to work with and was able to replace it immediately. The JDS20 turned out to be a highly accurate scale that comes with (2) 10 gram calibration weights to ensure the scales accuracy. I am very pleased with the scale and MeasuRite's costumer service. A great product from a great company.
Answer: The maximum weight is 20 graims. Place the two supplied 10 graim weights and calibrate. If you need more accuracy buy an expensive scale. This is a great accurate scale for the price.