Black Rubber Conical Stoppers (19mm, 2-Pack)

These high-quality, black rubber conical stoppers (size #19) are ideal for sealing flasks, test tubes, jars, and other laboratory glassware. Perfectly sized for flasks with a 22mm diameter, each stopper measures 30mm in height, with a larger diameter of 23mm and a smaller diameter of 17mm (19mm mid-diameter). Manufactured from a thermally and chemically resistant rubber compound (GOST 7852-76, 23-6-3), these stoppers withstand temperatures ranging from -8°C to +80°C. Please note: these stoppers have a rubber odor; consider this when using them for non-laboratory applications.