Heed the #3 (above) warning about not allowing them to snap together! YES....THEY WILL BREAK! And mine did. I guess there are different number ratings. The one I just lost had no rating, but it would almost leap to metallic items. This one does not. However, I mostly need it for finding wall studs, and these do work marginally. The delivery photo also shows it and other packages laying on our wet grass! It's been raining!
Not nearly as strong as the one I just lost!