Tape measure accessory

I have a tape measure, Don't know where I got it. .
It's maybe 10' long, a bit over 2" x 2", has a small level in the front and a yellow scribing tool at the other end. Fine.
It also has a piece of clear lucite 2" x 2" on the side with the Home Depot logo on it, and it's hinged at the top, but when the hinged part is closed, it has an empty space about 2 mm. thick between the lucite ann the black tape measure. What is this for?
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On Saturday, June 10, 2017 at 6:04:29 PM UTC-4, micky wrote:

Sometimes when you measure something, it is just a tiny bit too short or a tiny bit too long. That empty space is to store the little bits of long measurements for those times when the measurement comes up a little bit short.
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On 6/10/2017 6:58 PM, DerbyDad03 wrote:

Derby? You're going to go to hell for that one. ;)
Any fool knows that that's what those little zippered Cordura bags that HD sells are for. They hold more excess measurements and you're not as likely to lose them!
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In alt.home.repair, on Sat, 10 Jun 2017 19:41:45 -0500, Unquestionably

Okay. Good.

No, I think those are for people with sub-par tape measures.
BTW Home Depot doesn't list anything like this now and google images has nothing like it, home depot or not.
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wrote:

Home HARDWARE in Canada had something similar
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