This is the bolt pattern, also referred to as the stud pattern or PCD (which stands for pitch circle diameter). The PCD is measured in mm from the centre of one bolt hole to the centre of the next hole but one as shown.
For example with 5x120, 5 is the number of holes and 120mm is the measurement.

What is wheel PCD?

5x100

PCD or Bolt pattern

Here's a list of current 5x100 wheels in the Cades range.5x100 is the bolt pattern, also referred to as the stud pattern or PCD (which stands for pitch circle diameter). The wheels will only fit cars that require this wheel spec. Some popular cars are:

VW (older models) Golf MK4, New Beetle MK1, Bora, Lupo, Jetta
Audi (older models) A1, A2, A3, S1, S3
Seat (older models) Leon, Ibiza
Skoda (older models) Fabia, Octavia

Call us to see if it fits your car if it's not on the list.