#15 Solid Rubber Stopper (SRS)
The #15 Solid Rubber Stopper (SRS) is an undrilled pure laboratory stopper. The top diameter is 4 1/16" and the bottom diameter is 3 1/4". Perfect for using when fermentation is complete or if you are storing a clean and dry fermenter.
This is our largest stopper.
Our #15 stopper is also available as a #15 drilled rubber stopper (drs).