They are Hubbell spec grade receptacles or at least clones (doubt it). Our price is $5.30ea. But we buy lots of em.
Might be a little more if you buy over the counter. Maybe $7.
They are indeed good receptacles with higher clamping force than residential grade. Hospital grade has even higher clamping force. You gotta mean it when you “pull the plug….”
Losses are always higher at terminations. Heat. If you want all the benefit without changing your receptacle, treat prongs on cords with Anti Ox sparingly.
This is in my kit for audio installs and terminating cables. Especially outdoors. Works on line voltage just as well. One ounce tube lasts long time on small conductors. Dont need much.
https://www.amazon.ca/Gardner-Bende...und/dp/B000BOCBCA/ref=asc_df_B000BOCBCA/
