1 : Supply Air To Indoor Unit 
2 : Return Air From Indoor Unit 
3 : Air filter (s) 
4 : Electrical Box 
5 : Condensate Drain Hose 
6 : Inter-connecting refrigerant piping lines and electrical cables  
 between outdoor and indoor units. 
7 : Wired Room Controller ( Standard ) 
8 : Display & Receiver Panel for optional wireless remote control