Ductless Mini Split System Charging Vacuum Port Adapter Swivel Type, 5/16 Female, 1/4 Male SAE
New R410A Ductless Mini Split Systems are usually equipped with a different charging port size to avoid charging of wrong refrigerant into the system (i.e. R22). This new port size is 5/16" SAE and some gauge sets carry 1/4" SAE connectors. Port adapter converts the 5/16" SAE ports to use with 1/4" SAE gauge sets.