#4 Solid Rubber Stopper (SRS)
This #4 Solid Rubber Stopper (SRS) is a solid pure laboratory stopper. It has a top diameter of 1" and a bottom diameter of 13/16". It is solid and does not have a hole drilled in it, so it is a perfect stopper to use if fermentation has ceased or you are storing your clean and dried container.
This #4 SRS is also available as a #4 drilled rubber stopper (drs).