The key factor to remember here is that an American length will generally have five character spaces. The reasoning for that is a length can surpass inches and include feet depending on the fastener

0HC0250C01500Z5

The “01500” as listed below lets us know that the effective length of this HX Cap Screw is 1½. So now we have identified a steel  hex cap screw that is ¼ – 20 X 1½. “0HC0250C01500…”

1TS0014A01500HWSLZ

The “01500” lets us know that the effective length of this Tapping Screw  is 1 ½”. So now we have identified stainless steel #14 X 1½ TSA. “1TS0014A01500…”

1/16     00062

1/8       00125

3/16     00187

¼         00250

5/16     00312

3/8       00375

½         00500

9/16     00562

5/8       00625

¾         00750

7/8       00750

1          01000