Champion H10 is still a popular plug alot of older garden tractors with Kohler motors use them the old Ford flat head in the 8n tractors used them lots of other equipment too. H12 was the next hotter plug I believe Auto;ite 437 is same as h12 alot of people use the Autolite as they claim the new Champions are garbage I have saw alot of guys use the NGK but I think if they were alive Henry Ford or Ole Evinrude would send a lynch party if I put a Jap plug in one of these built in The USA or Canada of all North American steel wonders of boating and farming pleasure.
