This is a cap with an O-ring for the air conditioning valve of a standard passenger vehicle. ・Missing when purchasing a used car ・Missing after a regular inspection ・Cracked due to aging Please use this when replacement or installation is necessary. This is a set for the high-pressure side and the low-pressure side. If you need multiple sets, please refer to my other listings. Shipped via Yu-Yu Mercari anonymous delivery. R134a Car Air Conditioner Valve Replacement Maintenance High Pressure Low Pressure