Radium Engineering 1/2In Sae Male To 6An Male Converts 1/2" SAE male to 6AN maleThese adapter fittings are available in a variety of configurations. 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 connectionTo determine the required size, simply measure the outside diameter of the male fitting as shown below.0.3125 = 5/16"0.375 = 3/8"0.50 = 1/2"