This is a reed I designed for Revamped Outdoors' duck call. it may work in other applications as well.

His duck call can be found here: https://www.thingiverse.com/thing:3223209

10 mil is an imperial measurement roughly the equivalent of .25 mm. Because this is that thin, I had to ramp the resolution on my printer way up. I've also left it a little long and wide so it can be trimmed and tuned to your liking.

Update Dec. 10, 2018: I added a longer reed so I coud really dial in the sound I wanted.