Regex Exact Number of Characters

Regex Exact Number of Characters

How to limit the number of characters (alpha or numeric or anything)
Example I have (x can be any character)
name.xxx-XXX-XXXXXX-name
name.XXXXXXX-name
I want to exclude those of the first format and I thought I should do
something like
name.{7}*-name
I only want those with 7 characters between . and -