I have been asked four times what the difference is between a 543 and a 541 sense this POTM started. A 543 has a non-computing Veeder-Root. There were three versions of a non-computing Veeder-Root. The one that the 543 used is pictured below along with a 543 face. This non-computing V-R does not have the price wheels at the bottom. The lower large wheels are the price wheels on this V-R. Notice the price wheels do not have blinders. Also there is no variator below the head unit because that is the part that calculates the dollar amount. The drive connector is directly under the head unit. Also notice the knob next to it that is used to change the price on the price wheels. The last picture shows the gear above the knob. Almost all the 543s I have seen have been converted to computing V-Rs, that makes them a 541.