Swing-top bottles are made of glass and use swing-top closures—wire clamps or metal clasps paired with rubber gaskets—to create an airtight (hermetic) seal.
Features that reduce spills include narrower necks for controlled pouring and bases or faceted grips that improve handling stability while pouring.
Many listings warn that rubber gaskets should not contact pure oils or 100% fatty substances. One listing also advises leaving headspace (about 2 inches) from the top rather than filling to the brim to ensure proper sealing.
Some listings note that certain rubber gaskets aren’t suitable for carbonated drinks or direct contact with pure oils. At least one model explicitly states it can handle fermentation/carbonation pressure (noting it withstands up to 4 atm).
Hardware includes metal clamps/clasps/rings, rubber or plastic gaskets or lids, stainless-steel lid components, and occasional cork stoppers. The metal clamps/rings and rubber/hermetic caps are commonly recommended to be hand-washed rather than placed in the dishwasher to protect the seal and hardware.
