Bad specs?

Sometimes I wonder if I’m just really, really bad at my job. It’s to the point I have to ask for an outside set of eyes to make sure I’m not just bad at reading schematics and that instead someone doesn’t know how to write them.

I was just given a PDF of a part I was recently asked to make a 3D print of. Problem the first is I never actually made this part. It was done by someone else and I do not have any of the work files. Problem the second is why I’m here. I’m trying to follow the specs from a PDF that I would imagine is to scale, but…
This screenshot is a crop for the sake of both brevity and privacy. Nonetheless, you’ll get where this is all going wrong. The block is overall 6.75" in length and it’s supposed to have a total of 6 teeth (height of 0.4259", or about 7/16"), two of which are not full trapezoids because they’re on the edge. When I try to follow the dimensions given, this is the best I get:

Doesn’t look right, does it. When I try to correct it, this is still the best I can come up with:

I’ve written back to the person who gave me the document, but they haven’t gotten back to me. In the meantime, I’m staring at this PDF wondering if there’s simply something I’m missing. Thanks.

the only dimension i see missing is the height of the teeth. Rest of it had enough information, just repeat the width for the peaks and valleys.
cog.skp (440.3 KB)

Thanks, it makes more sense now. The height of the teeth was about 7/16" (0.4259).

It all adds up quite neatly. Height of teeth is missing.

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