Never worked.  Duds
Sadly these strips didn't work.  I don't know if I got a bad batch but they be we changed.  For weeks I waited to see a change before buying another brand...instant results.  I ran out of my new brand and decided to try a new package of them.  Nothing.  I bought new ones and tested several against this brand.  Still no change.  An expensive waste of money.
Rating: 1 stars