Subsurface Instruments makes high-quality underground Magnetic Subsurface Locators that are built for rugged and commercial use. They work great and are intended for locating Corner markers (iron or steel), Mag nails, PK nails, Valve and curb boxes, Iron and steel pipes, Well casings, Manhole covers, Steel drums and tanks, Septic tank handles, and Unexploded Ordnance (UXO). The Subsurface Instruments Company was founded and is managed by a Quality Assurance Engineer so quality has always been first on the list for all Subsurface Instruments products. Additionally, since 2010, Subsurface Instruments Incorporated has been the largest supplier to the US Department of Defense and UXO Operations. All Subsurface Magnetic Locators are back by a Manufacturers 7-Year Warranty.