the sssnake 1839 Adapter

It works fine, but I had a couple issues:

First, the 3.5mm side is not that smooth, you need to force the plug into it a bit at the end to secure it firmly

But a more serious issue is that the 3.5mm side is mono as well, meaning that if you plug a stereo headphone into it, you will hear only one channel. It kind of makes sense, but I did not expect this frankly.

Fir the above reason, unless you really need mono, I would suggest getting the stereo version instead.

I bought a bunch of those adapters in order to use them to send big patch cables from my eurorack directly to my audio interface. However the fit wasn't always good. Some times it would fit nice and stay at its place, other times it would fit loosely and move all the time, resulting in buzz and noise.

it's OK but poor quality.
I bought three seeing as they're cheap as chips. The input on one of these is very loose and often crackles. Probably better to spend a little more in this case.

Half of mine broke after connecting them for the first time. Pretty low quality, but they get the job done when they stay together.

Luse contact with 3.5mm jacks. It is better to find something more quality.