Amazfit Helio Strap replacement case

I wanted an easy way to swap the Amazfit Helio Strap between my wrist band and bicep band, without dealing with watch pins every time. This was the solution. It's ever so slightly smaller than the original, and it seemingly doesn't fit thick bands. It fits the original band perfectly, though. The “inside” part (where you put the Helio Strap) is designed by Ste3l, and is untouched by me, aside from making it very slightly narrower. The outside part is modified by me; I made the whole thing a little narrower, slightly less tall (admittedly, sacrificing some durability) and added watch pin holes. I printed with matte PLA, and it seems to do the job, but PETG is likely better. After printing, I recommend either sandpapering it, deburring it, or both. It's not strictly necessary, though.