its probably very close to 1/8" wider.. those 404 teeth seem HUGE compared to 3/8. growing up real close to Amish logging country, most loggers used an 046/460 with a 20" 404 bar. There was a few that ran 066/660's with a 24/25" for the big hardwoods.. they claimed it held an edge a ton longer with the wider tooth/kerf.
404 is great chain if you have a big enough motor, the problem with it is it will not bore with a 11 tooth sprocket so if you do a lot of boring in a logging situation you will need a 13 tooth sprocket nose.