Gardco’s new M/1S Holiday Detector, is for porosity detection in thin film coatings on conductive substrates such as tanks, concrete, and similar items. It has an ergonomic design with a twist-lock ground cable. It also features a strong fiberglass wand, a large sponge and a plastic sponge holder. This instrument conforms to NACE International RP0188 ASTM D5162-A, for low voltage holiday detection. The M/1S Holiday Detector is strong and the lightweight wand material reduces fatigue and will not bend. The new sponge material used for it is thick and strong. The sponge holder is plastic and will not damage coatings. There is easy battery access, and the unit uses common, easily found 9-v batteries. It has a regulated, 67.5-v DC output. The unit is a wet sponge-type holiday detector, and features a pushbutton calibration check. It has two resistance settings: 80k Ω for tanks and pipe, and 90k Ω for coatings on concrete. It is designed to be used on thin film coatings and is non-destructive. It has an impact resistant plastic case, stainless steel hardware, and a long-life ground cable.