No need for caps or a capper with these Flip cap bottles. Re-usable gasket cap assembly snaps firmly into position by means of a wire cam. Great for not only beer but also home made syrups and sauces. Bottles are 2 3/4" diameter x 10" tall with a capacity of 500ml. These bottles are sold by the 12 Pack.The swing cap design eliminates the need for separate bottle caps and cuts significantly down on the time you need for the bottling process. Spend more time drinking without sacrificing the freshness of your beer.