I have 3 FW, only one has a little 221 badge under the larger Singer badge, on the right front of the pillar. All three have the serial # on the underside, to the left rear corner as you'd sit at the machine. That is, if I was sitting at the machine and tipped it backwards to look at the bottom, the number is in the lower left corner. Btw, my Centennial serial # starts w/ EG, but it looks like E6. HTH