These are reusable, flip-top style beer bottles. Also called grolsch-style beer bottles. Their flip-top design simplifies the bottling process by eliminating the need for capping. The beer bottles are sealed by simply flipping the cap and rubber gasket onto the bottle's opening and clamping down the wire. No bottle caps. No cappers. They are made with a much thicker and stronger glass than typical 12 ounce beer bottles. They have a sturdy, steel wire assembly and thick rubber gaskets to complete the seal. You'll be able to reuse these beer bottles over again and again.