Kellyco Metal Detector Superstore The Kellyco Metal Detector brand is well-known in the metal detecting community and is synonymous with "the world's largest and oldest metal detector distributor." To first time metal detectorists, Kellyco is a one-stop shop for all their needs and has built a reputation by bundling unique packages to get everyone started on the right foot. Kellyco Metal Detectors has been the world's most trusted provider of treasure hunting equipment to both hobby and professional metal detectorists since 1955. Kellyco is headquartered in Winter Springs, Florida.