All UK distribs except Ilexa, buy their interfaces direct from Ross-Tech. Those that buy from us direct do not use certificates any longer. They use the short serial number. Ilexa, who manufactures interfaces under license, may still use certificate numbers on their units. Frankly, I am not sure they do because their software licensing uses the same short serial number. So, since 2004, not many, if any UK suppliers are using certificates.
There are other distributors throughout the world who may use a certificate number. Hence our web pages must still allow for them. Make sense?