1/2" Barbed adapter for cheap Submersible Pumps

Description:
These are adapters for Submersible pumps. There are 4 thread types to pick from

I own an ActiveAqua Submersible pump and I lost my other adapters for it . I searched everywhere to buy some adapters and I couldn't find the correct ones for my pump!
So, I bought a cheap pump on Amazon... Sadly the 1/2" or .51 barbed was a touch too small.

I decided to copy the adapter with 3d printing characteristics. I made the barb .526 which fits perfectly!
However, the threading was much harder to find.
I started off with 3/4-16 by counting the threads; about 14 to 16 per inch. Didn't fit!
Maybe it was Metric? The thread pitch was 1.8mmish which looked odd but maybe I was measuring it wrong? So I printed both M20 1.5 and 2 pitch. Correct size but not correct thread.
At a loss, because it wasn't 7/8" I didn't' know what to do??? until I figured it out. It was an M20 with 14 threads per inch. YES A MIX of both metric and US measurements.
Almost perfect... it was a bit lose
So 2A means loose fitting; which still tightens onto the pump. and 2B means tight. Its tight!

CORRECTION: The community informed me I wasn't looking at the correct type of threads. The M20-14 2b should be renamed to 1/2"NPS. Which is a straight Pipe threaded. It will take me a little time to fix this. Thank you community!

Hopefully this helps someone.

I spent less time making sure the other threads were correct. Mostly trying to find out what my pumps threads were. So, if your pump has a real M20 or 3/4-16 thread and it doesn't fit perfectly. I have included the CAD files for you to change it a bit.

Change Log:
Added 1/2"NPS "nut" as requested. For someone who wanted a female thread/Internal thread. What you will find on most of these little pumps. I include the SW/step files for you to edit it however you want.