A dynamic search coil using multiple harmonic wideband technology in a Double "D" configuration giving this coil increased sensitivity and greater depth. The 4.5" coil is masterful in searching out older more valuable coins in "worked out" areas. Thin necklaces and bracelets that are virtually impossible for other detectors and larger coil sizes to locate are usually found by the 4.5" DD coil. Rings are no match for this dynamic search coil. Small rings, gold rings, diamond rings are now being found!