This device works by measuring a skinfold with a small tab that "clicks" into place at the right tension and measurement. I used this 3 times and got consistent readings (that I thought were a bit low, but maybe they were right as I don't have a true recent measurement to compare against). After the third reading, however, the small tab required much less resistance to click to identify the right measurement and starting giving widely varying measurements.

I shipped back and had no problems returning, so I would shop again from this seller as they stood behind the product. I fault myself partly as this is a very inexpensive caliper and you get what you pay for. I would recommend buying a bit heavier duty one for others.Get more detail about Accu-Measure Fitness 3000 Personal Body Fat Tester.