General ToolsUV512C Digital Ultraviolet UVC Light Meter, 220 to 270 nM

This item works very well and accurately.

I had cataracts and got a lens called LAL+. These are adjustable after you get LAL lenses put in. The problem is that they make you wear UV400 certified glasses until you get the vision updates locked in. This meter is perfect for measuring your glasses and for measuring your environment. The UV frequency you have to avoid with the LAL lenses is between 200 and 400 NM. Specifically 165NM. This meter makes life easy. Great price. With this meter you can buy any UV400 certified pair of glasses and make sure they meet spec.

I have tested clothes, windows, windows with UV blocking film, helments, cloud cover, different times of the day, etc. I can't tell you about it's accuracy because I use it to compare to direct or indirect sunlight. I take a reading of something and compare it to the reading of the sun at that moment.Example: Helmet Visor up, rating over 7,000 while cloudy. Clear visor down, rating 32. That means it's cutting the UV over 200x. Funny, the smoke visor I have doesn't cut hardly any UV. Best clothes for severe sun, heavy cotton like Levi work shirts that are made out of denim. Better than any sunscreen. I have tested hats as well.

I like this digital UV meter because it lets me know how strong UV light will be from many sources. For example, somebody says the halogen light at your desk has very strong UV. After I bought this meter, I measured UV light from halogen bulb, CFL bulb, LED light bulb, incandescent light bulb at home and know exactly how much UV light emitted from them with compared to the UV light from the Sun. In this way, I can avoid the source that emits very strong UV light.This meter was built very well. It comes with a hard case although the hard case was not shown in the picture. The wand in this meter need a simple assembly by using five supplied screws but it is very easy. The measurement is very sensitive and the sampling rate seems high because I can see the measured value changes very quickly.It totally met my expectations so I give 5 stars.

General Tools UV513AB Digital UVC Meter, 280-400 nm [THIS IS COPIED FROM THE ITEM DESCRIPTION]I will return this item since the description of the item (copied and pasted above from the Amazon.com website today April 25, 2018 (also see a photo of the website description) does not match the item I received (see photos of item description on the packaging of the device received).There is a deceptive variance!As a novice to measuring UVA, UVB, and UVC, I read the description of the item on Amazon.com as a “UVC Meter.“ Perhaps others might fall for this description as I did. Most of us, I think, would believe that if something says it is a “UVC Meter” then that it means it is a UVC Meter.The item received is only for UVA and UVB measurements. VERY DECEPTIVE.How a seller can say that the item I received is a “UVC Meter“ is beyond comprehension and inexcusable! It seems like the description could be perceived as fraud, no?In case another person is interested, Wikipedia says that UVA spans the wavelength of 315-400 nm. UVB spans the wavelength of 280-325 nm. This item, therefore will measure both UVA and UVB from 280 to 400 nm. I take it from other reviews that separation of UVA measurements from UVB measurements may not be possible. Check on that if it is important.According to Wikipedia, UVC is measured at 100-280 nm, clearly well outside the capabilities of this item as described in its packaging.

Great product, well built. It has two "scales" so microwatts/cmsq and milliwatts/cm can be used depending on the intensity of light. Full summer sun in the 12 milliwatt range, while indoor, through curtains, clothing, etc. in 100's of microwatts. One can get a great "feel" for the difference in intensity using the two scales.If one keeps in mind that it's uvb sensitivity is only 20-30% of its uva sensitivity, one can still use it to compare the protection various materials provide for sun exposure, just by comparing the *relative* intensity of measurments with/without protection.It cannot "switch" between measuring uva, then uvb separately, event though the manual suggests it might be possible.

A great tool for those with sun photosensitivity. The absolute numbers on the scale mean little to me, but that is no problem; comparing direct light levels at high noon vs. afternoon vs. first light, through a car windshield and a car side window, through home windows, etc. to know how much relative UV is in each situation is very helpful!

Doesn't test the narrow spectrum of reptile lights, which was the sole purpose of this purchase. Can't tell if it works well with other applications. Seems well built, plug 'n' play, gives a quick measurement.