... 2,high quality 3.clear 4.ISO 9001:2000 Volumetric flasks laboratory glassware 1621 Volumetric Flask ground with glass stopper.1ml,2ml,5ml ... ,20ml,25ml,50ml,100ml,200ml,250ml,500ml,1000ml,2000ml. 1621 Volumetric Flask(with ground-in glass stopper or plastic stopper)Capacity ...