Two weeks after getting mine and experimenting, I finally found (between the "i" and "r" in "iron") a place where nails, paper clips are either rejected or break up, depending on the size of the item. Today I found a 14k gold thin chain with a good signal. Taking out my Silver umax and waving it in front of the coil-NOTHING. Putting the Silver in a/m mode-NOTHING. Finally, NONE of my detectors except a Garrett 60's model BFO would even give a weak signal. Increasing it between the "r" and "o" in "iron" stopped all the noise from the nails and it STILL gave a weak signal on the chain. To top that off, I found two pulltabs at about 4" in highly mineralized, iron-ore beneath a swing set that I had searched for over 20 years. Truly, this is Tesoro's best kept secret.