Stoppers - 1 Hole

These black, high percentage rubber stoppers are low in free sulfur and have a single hole to facilitate laboratory procedures. Stoppers sized 000 through 0 have a 3mm diameter hole; the size 1 stopper has a 4mm hole. Stopper sized as 2 and larger have a 5mm hole. Remain resilient and pliable under most laboratory conditions.
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