Rubber Stoppers, Solid #2, Pk/12

All of our black rubber stoppers are laboratory grade. Each is marked on top with the size number for easy identification.

These rubber stoppers contain a high percentage of pure rubber and are low in free sulfur. The stopper composition ensures resiliency and pliability over a long period and will withstand laboratory conditions without hardening.

The upper working temperature of these black rubber stoppers is 212°F.