After looking through a 1981 MW catalog, I agree that It may be a Huffy after all. When I'm wrong, I am man enough to admit It. Isn't any need to get like that. From the serial number that was posted, I believe It Is a 79 or 80 model year bike. As far as the serial number being different for a Huffy, some manufacturers (not every time) would stamp part of the said chain stores part number as part of the serial number. That's why I believe you could find a picture of this bike In one of the 79 or 80 MW catalogs. 81516 Is the model/part number and I believe the letter P stands for the year. Kenny.