Create a Dev Express "simplified regular expression"

Create a Dev Express "simplified regular expression"

I can't seem to find any documentation on what a "simplified regular
expression" is in the Dev Express Documentation. I have a credit card
field that validates the format of normal credit cards but some credit
cards have only 15 digits and I can't figure out how to make a variable
mask.
This is my current mask
SaveLiteral = False,
MaskType = Regular,
EditMask ='[*3-6]{1}[*0-9]{3}-[*0-9]{4}-[*0-9]{4}-[*0-9]{4}'
I am guessing that the last variable
'{4}'
needs to say something like
'{3-4}'
but when I do this I receive an error on initialization of the object.
If I am reading this right it says [allowed chars]{how many} static char
[allowed chars]{How many} ect
So that's why I think I need to figure out how to make a variable number
for the last size.