Managing condition in the auto-action tab

Hello, 
I am trying to set a condition in the auto action parameter to activate an email for all register demand that have a postal code starting by the 2 first digits. In France all zip code are about 54000 (this action is adapted for all club having as zip Code 54000 up to 54999. 

What is the correct way to set this condition referred to the following screen-shot 

Many Thank for your help 

Vincent

I would probably use a REGEXP condition for that. The below should work.

Field: ZIP_CODE_FIELD_HERE
Operator: Is REGEX
Value: /^54/

Thanks a lot