BMW X5

This measures how far the wheel’s mounting surface is from its centerline. Positive offset means the mounting surface is toward the front of the wheel, while negative offset means it’s toward the back. Proper offset is crucial for ensuring that the wheel sits correctly within the wheel arch and aligns with the suspension components.

This is the diameter of the circle formed by the wheel bolt holes. It indicates how many bolts/studs there are and their spacing. For example, a PCD of 5x114.3 means there are 5 bolts and the diameter of the circle is 114.3 mm.

This is the diameter of the hole in the center of the wheel that fits over the hub. A proper CB ensures that the wheel is centered on the hub, which is vital for vehicle stability and safety.