"Floor Flange" or something similar for 1/2 copper pipe
This is an Drop Elbow (upside down for your use), most commonly used for wall penetrations...showerhead arms, tub faucets, washing machine supplies, etc. I don't know of any other types that you'd actually screw to the floor &amp; haven't ever seen one.

Presuming your hole is tight to the wall or baseboard, you might be able to attach this to your wall or baseboard with either a direct connect flexible line or a single compression fitting. Anything more would likely get crushed by the fridge. But a screw in elbow fitting to convert to vertical may work for your situation. However, elevating the fridge's tube connection that's already set-out much may put it in threat of being crushed, so be careful &amp; test it out gently.



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Male solder-on or sweat-on. My preferred floor lock-in fitting. Threads are exposed for thread inspection, easy Teflon taping, more precise leak detection, female reducing adapters are more common &amp; flexible lines come with direct attachment ends.



Female solder-on or sweat-on. Nothing really wrong with this. I just don't find much of a selection to accommodate it in the big stores.



All three would be first soldered onto the pipe you drop in the floor. It's ill-advised to feed a pipe up &amp; then later solder on a fitting that's close to a wall, especially when so easily avoidable.

Your pipe or elbow beneath the floor would prevent or limit vertical movement &amp; a hole drilled for the pipe diameter instead of for the fitting's shoulder would raise the fitting for easier future flexible line replacements &amp; stop downward movement to avoid stressing of the piping beneath the floor.