You mean something like this? Scroll down to garden hose to male flare attachment.
Or do you mean something else? This site has many other fittings that are hard to find elsewhere and you might just find it on the other pages of this site.
If not maybe you can elaborate some more on what you are looking for.
My Brew Rig Build
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"Perfection is unobtainable, but if you chase perfection you can catch excellence."- Vince Lombardi