This system allows you to filter or redirect ozone depending on your needs. If all you need to do is filter ozone at the end of a setup so it doesn't enter the room, you can use the single Luer connection. If you want to filter ozone until it's needed and then redirect it to your application, use the stopcock.
The stainless steel construction will not break or leak. Simply unscrew the cap to replace media when needed. The fitting is milled into the cap for strength and to eliminate leaks.