A pocket penetrometer is required by OSHA on all excavation jobs. The AMS pocket penetrometer will help protect you from costly lawsuits and construction delays by providing accurate measurements of the compressive soil strength. This 6-1/4in unit is spring-operated, and it is measures strength in tons/sq. ft. or kg/sq. cm by pushing a 1/4in diameter loading piston into soil to a depth of 0.25in. The end area is 0.05 in/sq. Compressive load is indicated by reading a scale on the piston barrel. A friction ring indicates maximum reading. Made of anodized aluminum. An Allen wrench and plastic carrying case with belt loop are included. A special 1in-diameter adapter foot is available as an option for use in very sensitive soils.