1 7/16" x 1 1/8" (36.6 x 28.7 mm) drilled universal stopper
This tapered rubber stopper has a longer taper for a better seal. The lip around the top prevents the stopper from falling into a carboy. It fits all 3, 5, 6 and 6.5 gallon glass carboys.
This stopper does not fit plastic carboys. A Medium Drilled Universal Stopper is required.