A : Geometry value
B : Support value
C : Identical axle
I : OE wheel with a 30 ET
II : With new wheels, ET = 0
Spigot: part in the centre of the hub that you rest inside the centre of the wheel. It is different for each vehicle.
Wheel width: generally, a model in 17' will always have the same width. The tuning wheel never has the same width and same offset (ET) as the orginal alloy wheel.
Number of holes: 4 or 5 holes for ars
PCD: diameter of the studs from the centre of the wheel.
Offset (ET): is the distance between the imaginary centreline of the wheel (as viewed from behind the wheel as it would roll away from you) and the inside face that bolts up against the wheel hub on the car. Generally goeas from ET15 to ET60 (except in extreme tuning where ET0 is fitted). Higher the offset is, less materia there is betwen the hub et wheel's axle. It is usually not written on the orginal steel wheel and is not necessary to place an order.
Lip depth: rim border depth.