Made in USA. Replace the unsightly plastic or mismatched service port caps on your A/C system with our new Pure Stealth Black Aluminum Service Port Caps. Simple screw-on installation. An O-ring inside of the cap seals your service port and protects the schrader valve from debris. These caps will fit all Vintage Air standard barrier or reduced barrier service port fittings with 5/16-24 internal threads. These caps will Not work on Vintage Air E-Z Clip or ProLine service ports fittings which have metric internal threads.