Seta Glass Hydrometers conform to ASTM - IP or BS specifications for determining the Relative Density, Specific or API Gravity of crude or liquid petroleum products. Manufactured from sodalime-silicate glass with a linear coefficient of expansion of 9.2 x 10 6, they are shot-poised, and calibrated for use in liquids of LOW surface tension (15 to 34 dynes/cm).
