Universal Plastic Carboy Breathable Bung | CellarScience®

This CellarScience Bung has a ridge to keep it from getting sucked in and self-sealing vent holes to let air out but not in. They have a gentle taper, so they don’t slip out during use.  They are also very easy to clean and sanitize. Replaces Stopper Sizes #8, #9

• Stopper Measurements: 1.36″ x 1.89″ (34.5 mm x 48 mm)
• The flapper stopper protrudes roughly 2.5″ from the stopper to allow for easy assembly