Why There Are 21 Serrations on Every Beer Bottle Cap?

Do you have ever noticed how many serrations there are on the caps of beer bottles? As a trivia,21 is the most common number of serrations of the beer bottles’caps.

(Image Source:Creative Package)

Well,in the early 20th century, there were many kinds of serrations on beer bottle caps, including 23,24 sawteeth,etc. But it was later found that the bottle cap with 24 serrations was difficult to open and could easily damage the bottle mouth.

In order to improve the sealing and ease of use of the bottle cap, the bottle caps with 21 serrations were finally determined to be the easiest and safest to open. The bottle caps with 21 serrations are better adapted to industrial production and provide proper sealing and ease of use. The design combines high occlusion with adequate safety. The 21 serrations can make the contact area of each fold on the cap as large as possible, increasing the friction between the cap and the cap to ensure firm.In addition, the 21 serrations on the caps are ergonomic and do not scratch the finger when open. 

This design is gradually adopted by various beer manufacturers, and has become a common standard beer bottle cap on the market.Now wherever you are in any city of the world the beer bottle you see always have 21 serrations on its cap,and you can count the serrations of the cap carefully next time you drink beer to find the truth.

(Image Source:Idea Bottles)

But not every serrated cap of beer bottle is easy to be opened.It generally depends on the material used.As we mentioned before,the caps always be designed with 21 serrations for a secure grip.Beer bottle’s caps that made from high-quality materials can help withstand even the most demanding conditions.Thick metal are sturdy enough to keep the beer fresh and avoid any accidental impact that may pour the content out.