Measuring tapes have a few features that a lot of people don't seem to know about.
The notch in the metal clip is so you can pop a nail into something and hook the tape onto the nail to measure on your own.
You can also hook it onto a nail, hold a pencil at a measurement you want, and use it to draw a circle.
That metal clip is also serrated so that you can use it to scrape a mark in something like wood when you don't have a pencil handy.
Also, in relation to the metal clip, you may notice it's loose. It's loose by exactly the thickness of the clip so that you get a correct measurement whether you're measuring from inside or outside.
Finally, if you look at the side of the tape, you'll notice a measurement is written there, like 70mm.
This is the length of the measuring tape housing itself.
The reason for this is so that you can sit the tape against a window frame, for instance, and measure to the other end.
Now just take the measurement and add the measurement on the housing.
Most people seem to just bend the tape into the corner, but that's just cumbersome and likely inaccurate.
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