Supports the following standards: ASTM D3282, ASTM D422, ASTM C88, ASTM D7928, AASHTO T88 Soil hydrometers measure the distribution of soil particle sizes by analyzing suspended solids in sedimentation cylinders. Soil Hydrometer A— H-4241: Seamless, symmetrical stem and bulb do not vary in diameter. One-piece ballast is secured to lower part of the body. Guaranteed calibration accuracy eliminates errors due to variable dilution. H-4241 uses ASTM 152 H scale, graduated to read in grams per liter (g/L) of suspension and has a range of -5 to +60g/L in 1g/L divisions at 68°F (20°C). Total length: 11" (280mm). Soil Hydrometer B—H-4242: Seamless, symmetrical stem and bulb do not vary in diameter. One-piece ballast is secured to lower part of the body. Guaranteed calibration accuracy eliminates errors due to variable dilution. H-4242 uses ASTM 151 H scale, graduated to read specific gravity with a range of 0.995 to 1.038 in 0.001 divisions at 68°F (20°C). Total length: 11" (280mm). Total length: 11" (280mm).