Shavers, Dempsey, Zarate, Tyson, Hearns, Duran, Pacquaio down under 120. WW Robinson, Foreman, WW Robinson, Middleweight Roy Jones Jr., Julain Jackson, Gerald McClellan, Nigel Benn, Joe Louis there are a lot more, but Zarate in particular is probably the hardest puncher p4p the sport has ever seen.

Guys like marciano weren't the biggest ko type fighters, he wore out a lot guys over several rounds. He was a harder p4p puncher than Cotto, but it was the same idea.