The 12 Drilled Rubber Stopper (DRS) is a pure white gum laboratory stopper. The top diameter is 2.5625″, the bottom diameter is 2.125″, and it has a 3/8″ hole drilled in the center, the perfect size for an
airlock
.
The 12 rubber stopper is also available as a 12 Solid Rubber Stopper (SRS).
