HC = high current.
I see 20 amp being mentioned on some cables. I am looking at audiomart for used cables. I guess it means that they are thicker gauge and can carry higher current. But I am not sure if they are better than 15 amp regular cords. Also, perhaps, there are different recommendations for power conditioner vs amp vs other gears.
I am not an influencer or affiliated with Puritan. Just highlighted my preference.