we can check the AC hose Nipple Nut sizes, it should be more carefully.In China we often use the 30# tool to install the Nut, however the tool# should be 29# in EU countries.So when we are applying for those AC connectors, we must inspect the Fitting Nut Size. Attached the picture....

AC STAR-FITTING is a special type of fitting which does not use any crimp ferrules or fixed holder.when we install the type fitting, it is more easy. however we have to be more careful during producing.now let us show the processing....

Plating Zinc for air connector fittings...