The Magnetic Ruler is a battery-operated (6 ea. AAA), data-collection device for the K-100 Dynamic Cone Penetrometer (DCP) Kits allowing a single operator to complete tests. It displays depth, blows, mm/blow, cumulative mm/blow, and cumulative blow/inch in SI and English. The correlations are CBR (California Bearing Ratio) in % and bearing capacity in pounds per square foot (PSF). A flash drive records the data, information entered by the operator, and date and time for each test via a USB port. The sensitive electronics on the vertical scale detect the position of the upper attachment, which slides freely over the vertical scale and is fastened to the drive rod at the other end. This product is accurate to 1 mm. A field printer is an available option that allows printing of the results prior to moving to the next test location. Each Magnetic Ruler comes with a calibrated K-100 Upper Attachment (Part # K530), USB Flash Drive, and batteries.