This is my first try at testing with the Dr. Otek pin pointer. The results are: copper cent-1 1/14" , buff nickel-1 3/4", silver dime-1 1/4" ,SL half a little over 1 3/4" , Peace $-2" , 1/2" lead ball smashed - 1 1 /2" . This is by no means a totally accurate test. All I did was Mark each 1\2" on a piece of paper and put the coin at 0 and move the pin pointer toward the coin. If it works like that in the field I'll be satisfied. It seems to be well constructed. Hopefully it will last. It vibrates, no audio. It signifies the distance of the target by a colored light red to green to to blue to light blue. Light blue is closest to the target. As I have stated before, this is my first pin pointer so I have nothing to compare it to. It also states that it is water proof. I'd like to use it a few times before I check that. Hope this helps.