Spherical Seperating Funnel 1.With Glass Sttopper and Glass Door 2.High Quality 3.Have a low coefficient ... Seperating Funnel Spherical Shape With Glass Door ,Standardized hollow key and key retaining device,with standard ground glass stopperThe Glass Funnel is made of ... the coefficient of expansion of 3.3 high-borosilicate glass.BJTY glass with the best chemical stability, low expansion coefficient, ...