Adapter 1/2" OT - 1/4" IT

For a small renewable energy project, which I'am about to start, I want to use an old manometer which has 1/4" other thread. To connect to all of my other garden quick couplings I had to get an adpter from 1/4" inner thread to 1/2" outher thread.

Note: Until now I have never tested if this will hold any pressure at all so do not use this in any permanent installation!