CZ threaded muzzle

[Uncle Alvah]

I was looking at the 2007 CZ catalog.
One of the new offerings is the 452 .22 rifle, with a 16" barrel.
The description says that it has "a threaded muzzle with a thread protector".
What is the purpose of the threaded muzzle?

 

[Medusa]

Umm, to screw a compatible silencer on? Or for attaching a tactically black bottlecap - to prevent the elements from getting into the barrel and ruining it.. Can't make up my mind between those 2 options.