Short length stopper is conical on the underside and has a hole approximately 1.6 mm in diameter to allow air to escape

·         Conical shape offers greater stability

·         Determines specific gravity for road oils, road tars, soft tar pitches, and asphalt cements (ASTM D70); drying oils, varnishes, resins, and related materials (ASTM D1963); water and brine (ASTM D1429); and insulating varnishes (ASTM D115)

·         Manufactured from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements