theres 3 hose fittings..2 top 1 bottom. on the side with 2 ..this big one goes to the wastegate....what connects to the other 2 fittings?

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1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero