aftermarket air filter

after my air box is removed and main feed to engine has filter on it there is still a hose left now that theres no airbox for it to atach to. it went the the front side of the box is an inch in diamiter but i couldnt really find where it came from or anr dramatic air movment from it wile reving ... what does this mistery hose do?

after my air box is removed and main feed to engine has filter on it there is still a hose left now that theres no airbox for it to atach to. it went the the front side of the box is an inch in diamiter but i couldnt really find where it came from or anr dramatic air movment from it wile reving ... what does this mistery hose do?

It helps during cold start (only). It has a valve that opens upon start up. Its just to help pass us emmisions.