8x210 is a commercial pattern used on heavier chassis. You will find it on medium-duty and commercial trucks. We stock 314 wheels drilled 8x210.
Measuring is simple: count the studs, then measure the diameter of the circle they sit on. Five studs are measured from the far edge of one hole to the center of the one two holes away; six or eight studs across opposite centers. Ordering the wrong pattern is the most common fitment mistake — if your measurement falls between two patterns, confirm with the vehicle's spec sheet first.