Penetrometer Set is used to determine penetration resistance of fine grained soils. The penetrometer consists of a spring dynamometer with a scale on the stem of the handle graduated from 10—130lbf (45—580N) in increments of 2lbf (9N). A sliding ring on the stem gives shear strength obtained in the test. Model HM-560 basic set includes interchangeable threaded needles with areas square inches (square centimeters); 1 (6.45), 3/4 (4.84), 1/2 (3.23), 1/3 (2.15), 1/5 (1.29), 1/10 (0.65), 1/20 (0.32), 1/30 (0.22) and 1/40 (0.16). Replacement needles are available, please inquire. Set comes in attractive foam-lined wooden box with carrying handle.