Look inside almost any wheel and you should find various markings that give you pertinent information on the wheel. Typically, they’re marked on the rim. Just for conversation sake, we’ll take into consideration a wheel that is marked “19x7J ET38.” The first number is quite obvious and represents that the wheel is 19 inches in diameter, while “7” is the width of the wheel and measured from the distance between the flanges that support the bead. The “J” refers to the shape of that flange; easier to understand if you imagine a steel wheel on which the lip is rolled over like a J. “ET” may or may not be present, and if you do see it it’s the abbreviation of einpress tief, German that translates literally as “pushed in depth,” or offset. The “38” is the offset measurement.