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 "?

63,914 Measure Marks Images, Stock Photos, 3D objects, & Vectors

How to Read a Tape Measure: the Definitive Guide - My Simpatico Life

My tape measure has markings that are half the actual distance

How to Read a Tape Measure: the Definitive Guide - My Simpatico Life

How to use a Tape Measure and read Fractions Easily

How To Read A Tape Measure + Free PDF Printable - DecorHint

1,500+ Tape Measure Markings Stock Illustrations, Royalty-Free Vector Graphics & Clip Art - iStock

How to read an imperial unit's tape measure - Quora

HART 30-Foot Autolock Tape Measure, Fraction Markings

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