please identify a/c refrigerant recharge valve - Audi

hi everyone,

i have audi a4 3.0 quattro and now i am going to

add some refrigerant myself.

please take a look the picture

http://rr444.myphotoalbum.com/view_photo.php?set_albumName=album01&id=ac1


is the one is the blue circle or the other one in the

red circle that i should go?


thank you in advance



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