I guess if you need to distinguish it specifically at a 12 sided shape, then, 'deci back' or similar (dec back. dodec etc)
If not. then 'poly back' will do!

Stewart

: I posted this photo below, but wanted to repost it here (at the
: top of the page), so that we focus on the question, "what
: shall we cal it?".

: This is the case-back on an early Carrera. The angled edges allow
: the screw-back case to be gripped and opened. Mistakenly, I had
: been calling it a "hex-back" (which is incorrect, as
: this case-back has 12 sides, whereas a hexagon has six sides).

: So what shall we call it? "Polygon-back" is a
: techinically accurate, and seems good to me, though the phrase
: is a bit cumbersome. I am guessing that a watchmaker or engineer
: will be able to tell us what this style of case-opening
: arrangement is actually called, so until then I am happy with
: "polygon-back".

: Do any readers have different suggestions? Any idea what the
: correct engineering / technical term might be?

: Thanks,

: Jeff

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