Mine has a genuine Nissan snorkel , when I 1st bought it 2 yrs ago ( it's a 2002 model ) I did the plastic bag check & it continued to run & I could hear the air sucking in inside the guard so off with the wheel , inner guard etc ' check it out . From memory where ever there are joins the plastic sort of fits inside the other piece with a foam rubber type seal between - pretty ordinary set up really , I'm going to make 1 out of stainless pipe with all the external bends welded on but internally the bends will be silicon hose clamped onto the stainless . That's the plan anyway . Mainly because I know it'll be right - the current setup is a constant worry whether or not the urethane is still sealing properly etc . 1 of the main problem points I found is where the plastic pipe comes through into the air box