?Fast installation,simple,smart and space saving ； ?Diversified types to meet all pneumatic needs ； ?Even installed , the plastic part can be freely turned； ?The release ring is made round or oval shape(customer choice).the oval onefacilitates disconneting tubel； ?All taper pipe threads are pre-coated with tetrafluoroethlene leak protective coating; ?All cilindrical thread are standand with O-ring seals.