This is a really nice detector for the saltwater beaches here in Florida. I have both the 8" and 10" coil versions . The 3 tones give you a good idea as to what the target may be . Low tone is iron . Med tone aluminum or gold . High pitch coin , including nickels. Unlike some other water detectors the cz- 21 comes with a comfortable straight shaft for ease of use when wading or diving. A real winner for those that beach hunt .