Some molded carpets come with jute backing where your feet rest on the floor pans.
People restoring classic cars will often freshen up the interior by putting in new carpet to cover new floor pans.
There are several styles of molded carpet, the most popular include 80-20 loop, cutpile and essex.
Essex is a longer more plush version of cut pile carpet.
Some cars such as the Ford Mustang Mach 1 had two heel pads from the factory.