fisher cz-3d metal detector fisher the cz-3d is engineered to provide maximum success on old coins while retaining the best possible ratio of good targets vs. trash targets. with its new enhanced mode the cz-3d more easily finds older coins such as nickels, indian head pennies, gold coins, older silver coins, etc. cz-3d pulls these older coins out of the pull-tab audio range where they are normally located due to older coins having a longer different matrix rate of decay. without the cz-3d enhanced mode, these older coins would sound the sam