The Survey Encounter, made by Tramex, is the world's most advanced meter for finding moisture behind and underneath wood, plaster, brick, carpeting, vinyl flooring, ceramic tile - even the backside of drywall. The Survey Encounter operates on the principle of non-destructive electrical impedance to give accurate non-destructive moisture readings from five to thirty percent in wood and relative readings for walls, rooking and other construction materials. You will never have to drill a hole in a wall or floor again. Move the meter along the surface of any construction material and track a leak to its source. The Survey Encounter stores up to 625 readings in 25 files. It rents with software that downloads data to a PC for spreadsheet analysis on graphs and charts.