United Scientific Supplies RST6-H2 Rubber Stoppers, Two-Hole, #6

These black stoppers are made of solid natural rubber that stays pliable over a long period of time. Ideal for use with non-aggressive or concentrated solutions. Low sulfur content. Withstand temperatures from -25 to 70°C (-13 to 158°F). Each stopper has its size marked in raised figures. Sold as one-pound bags.

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