Bests & Worsts Reviews from Amazon

As a thermometer, it seems to work fine. But if you're using it in a acrylic tank, DON'T USE THE SUCTION CUP! It left two permanent ring shaped marks on my tank, after about a month of use. I can't get them off by scrubbing or rubbing, or even scratching with my fingernails. (added a picture of the mark to the product images) Be warned!