Wheel fitment requires the bolt pattern of the wheel to match the vehicle. The bolt pattern is the number of lugs and the diameter of the imaginary circle they create.
The bolt pattern is expressed as the number of bolts "By" or "On" the diameter of the imaginary circle they form.
5 X 114.3MM would be expressed as "5 by 114.3" or "5 on 114.3"
The diameter may be stated in millimeters or inches. Each is correct and may be converted to the other. There are 25.4mm per inch.
5 x 4.5 inches is the same as 5 x 114.3mm (4.5 x 25.4 = 114.3)
5 x 114.3 mm is the same as 5x4.5 inches (114.3 / 25.4 = 4.5)
Measuring a bolt pattern is easy!
An even number of holes creates a perfect circle and is measured from the center of one hole across to the center of the opposite hole. An odd number of holes is measured from the back of one hole to the center of the second hole. This adjusts for the imperfect circle.
More about bolt patterns:
Bolt pattern is also known as pitch circle diameter (PCD). A variety of gauges are available to measure bolt patterns. Visit https://www.gorilla-auto.com/
Some wheels have multiple bolt patterns and are referred to as dual fit or dual drill. This allows one wheel to fit more vehicle applications.