This connector increases the possibilities of your breath control play because it increases breathing resistance and the bubbling sound is also an exciting add-on. The more liquid you put in the bottle, the harder you have to work to inhale. Another fun option is to fill it with another favorite liquid, or to add a few drops of poppers.
Breath control play is a lot of fun, especially in combination with bondage. But safety first: solo breath play is a known killer in the kink scene. NEVER play alone. NEVER leave your partner unattended, not even for a minute