tire sizes do not match correctly
Tire sizing is a mess. Read it and weep.
&quot;700&quot; or more properly &quot;700C&quot; is derived from an old French tire-sizing system; the number indicates the outside diameter of the tire in that system (700 mm), and the &quot;C&quot; indicates the width of a tire under that system (meaning &quot;wide,&quot;). &quot;622&quot; represents the bead seat diameter (or, approximately, the inside diameter of the tire) of a 700C tire, under the modern ETRTO sizing system. These days we use &quot;700C&quot; as the name for a size with a tenuous relationship to its original measurements (curiously, 700C has mostly survived as the name of the size for skinny road tires); &quot;622&quot; is more precise.
You'll see that these tires are also called 28&quot; on that table, which is extra-fun because they're slightly smaller than 27&quot; tires (which have become very uncommon), but have exactly the same bead-seat diameter as tires labeled 29&quot; (used on mountain bikes).
Why the widths (38/40) aren't the same is less clear to me. Maybe the company has their own system for measuring widths that is slightly different from the ETRTO system.