Fluval 407 part ID

[scotts8826]

I was cleaning my Fluval 407 and found this item in the canister. Anyone with an idea where it goes? It is made of rubber/silicone.

 

[Idech]

I haven’t used my 407 in 3 years. I can see it in my head but not enough to know what it is. I do know it’s to close some type of hose somewhere. Maybe on the head part.

I’ll let you know if it comes back.

I found it after watching a Fluval video. This is where it goes I believe (blue rectangle) :