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Keep your chemistry experiments clean and safe with rubber stoppers! These sturdy plugs fit tightly into test tubes or flasks to prevent chemical leaks and spills.
Some lab work requires a full setup of glassware. You’ll need one- or two-hole rubber stoppers for those experiments, and use 5 mm glass tubing to connect to other apparatus.
For small test tubes use #00 stoppers. Use #0 for large test tubes, and #1 for extra large. Use #6.5 stoppers for 250 ml flasks. Use a cork borer to drill holes in the corks.
And use our quick & easy guide to identify which size of rubber stopper you need.