Stopper Stopper Size 22 Bottom Diameter 20 mm Top Diameter 22 mm Overall Height 50 mm Material Borosilicate Glass Product Type Stopper Color Clear Autoclavable Yes Number of Holes 0 Standards Not Applicable Special Features Ground Joints for ASTM Standard Flasks Resists Abrasion and Water For Labware Type Jointed Glassware Liner Material Borosilicate 3.3 Glass