Bolt pattern or lug pattern or bolt circle
is determined by the
number of bolt holes and the bolt circle diameter.
Hub Diameter or center bore is the hole at the center of the
Rear spacing or back spacing is the distance from the
backside of the wheel mounting pad to the outside of the rim flange.
Offset: The distance from the centerline of the wheel to the
mounting surface of the wheel.
Negative offset: When the back of the bolt pad is closer to
the inside of the wheel; when mounting surface is inboard of the rim centerline.
Positive offset: When the back of the bolt pad is closer to
the street side of the wheel; when the mounting surface is outboard of the rim centerline.