It is NOT code required, but I always use it. I coat the screw threads of AL terminations and lugs as well.

I too always use it regardless of size.

"It is NOT code required, but I always use it."

I have not checked the listings in a long time, but at least at one point the listing required anti-ox on stranded aluminum for a couple wire types.

You have to obey the listing.

A quick look in the White Book under Thermoset-insulated wire (ZKST) and Thermoplastic-insulated wire (ZLGR) does not show any requirement for using anti-oxidant on the terminations. Any manufacturer supplied instructions requiring the use of anti-oxidant would be in the form of a tag attached to the reel which you would never see unless you bought the whole reel.

Even if there is no requirement for anti-oxidant, my experience is that connections made without the inhibitor are more likely to fail than connections made with it. For the 2â¡ or less that it costs per termination, I can think of no good reason to forego its use.

Many of the crimp type connectors already have 'goop'
in them when you buy them.