The 2 on the left appear to be 5/8" inserts, while the one on the far right appears to be a 1/2" inserts.

The rest of this is probably TMI, but here goes ---
As you're aware (but for others) inserts are measured at the outer edge of the chip. The smallest ones start at 1/8' each, then graduate in 1/8" increments. So ... 1/8" then 1/4" then 3/8" then 1/2" then 5/8" then 3/4". Not sure if there's a 7/8" option (I don't think so) or if it jumps to 1". And it goes even beyond that.

Most fill a notch shape, but some can be half-moon shaped and there's a difference in the shape of the inner curve too. If it follows the outer curve, it's considered an inverse or offset curve (used in some older chips, like Christy & Jones). These days, the inside of inserts is usually a simple straight line, or close to it.

There's quite a a few other terms, sometimes used (or not), like parallel inserts (such as 4 sets of 3x1/16" inserts), inset in inserts, v-shaped inserts or split-V's and more. These descriptive notations used to be more important prior to having scanners and photo picture of chips. There's still more, but I'll end it there.

If you want to do some (sort of) interesting math, pull out the old geometry textbook that calculates a circle's circumference is the diameter (or radius) is known. Diameter is just radius x 2. Circumference is diameter x pi (in which pi =3.142. With the computer, or asking google you can easily calculate that the old style chips, marked as 1-9/16" diameter on the boxes, means that the circumference is 1.5625" x 3.142 = 4.9" (or rounded to 5 inches circumference).

So, if you have 3 inserts that are 5/8" each (= total of 15/8", or rounded to just under 2 inches), you have a chip with about 3" total of base color + about 2" total of the inserts color (for all 3 inserts combined) = the total for a 5 inch circumference chips. As a ratio, it about 3/5 base color and 2/5 insert color. Even without measuring, you can visualize that ratio pretty easily.

Also, you can substitute using millimeters (mm) instead of fractional inches, which is more common these days.

Class dismissed, I'm outta here.