Cork Stoppers

Cork stoppers provide reliable, renewable sealing for bottles, flasks, tubes, and custom hardware projects. Made from the bark of cork oak or high-performance synthetics, these stoppers compress to conform to openings, delivering an airtight, leak-resistant seal that’s quiet, non-marring, and easy to install. Use cork plugs for lab glassware, homebrewing carboys and fermentation locks, winemaking, chemical storage, craft jars, powder-coating or finishing masks, and as vibration-damping feet or spacers in woodworking and specialty hardware setups.

Choose among natural cork for food and beverage contact, agglomerated cork for budget-friendly general use, and synthetic stoppers for higher consistency, moisture resistance, and extended service life. Options include tapered corks, straight plugs, and drilled stoppers with one or two holes for tubing, airlocks, and vents. Many are food-safe and meet FDA requirements; look for product listings that specify compliance and temperature ratings.

Sizing is simple: measure the container’s inner diameter and select a stopper whose large (top) diameter is slightly greater than the opening. The taper provides a snug friction fit; plan for light compression rather than force. For tubing, match the drilled hole to the outer diameter of the hose. If you’re unsure, assorted size kits cover most lab glass, vials, jars, and industrial containers.

Practical tips:
- Clean, dry surfaces before installation; twist, don’t push straight, for smoother seating.
- Avoid over-compressing to prevent splitting; replace any stopper that shows cracks.
- Sanitize food-contact stoppers with approved methods; let them dry fully before reuse.
- For long-term storage, consider a thin food-safe silicone coating to enhance sealing.

Cork stoppers are easy to cut, sand, or drill with cork borers and reamers, making custom fits straightforward. Their low weight, acoustic damping, and sustainability profile make them a smart choice for labs, workshops, and makers who value a tight seal, clean finish, and low-maintenance performance.