Radium 3/8in SAE Female to 6AN Male, Low Profile These adapter fittings are available in 5/16″, 3/8″, and 1/2″ sizes. They push-on and secure to most modern USA, European, Japanese, etc. fuel injection systems and are used to convert an OEM SAE Quick Connect connection. These adapter fittings are available in 5/16″, 3/8″, and 1/2″ sizes. They push-on and secure to most modern USA, European, Japanese, etc. fuel injection systems and are used to convert an OEM SAE Quick Connect connection.