Tape measure markings

I know that the red numbers found every 16" on a tape measure are for laying out studs in a wall. But what is the little diamond shape at 193⁄16 "?

All about reading the tape measure - SewGuide

Tape Measure Markings: What Are They For? - Pro Tool Reviews

Measuring scale, marking for ruler, length measurement scale chart

How to Read a Tape Measure : 4 Steps (with Pictures) - Instructables

What Are Tape Measure Markings For? - Defiance Tools

Ever Wondered What All The Markings On A Measuring Tape Are For

Tape Measure Tips and Tricks - What is that marking?

Detail of a tape measure at the 2 Metre mark Stock Photo - Alamy

Tape Measure Markings Not The Same

Tape Measure Markings: What Are They For? - Pro Tool Reviews

Tape Measure Markings: A Deep Dive – Love & Renovations

Tape Measure stock photo. Image of inches, ruler, fractions - 5249382

Tape Measure Markings: What Are They For? - Pro Tool Reviews

How to Read a Tape Measure the Easy Way & Free Printable! - Angela

Flexible Ruler Marker Corrosion-prevention Ruler Positioning Tool