How to represent a fix number of repeats in regular expression?

Is there a better way to represent a fix amount of repeats in a regular expression?

For example, if I just want to match exactly 14 letters/digits, I am using ^\w\w\w\w\w\w\w\w\w\w\w\w\w\w$ which will match a word like UNL075BE499135 and not match UNL075BE499135AAA is there a handy way to do it? I am currently doing it in Java, but I guess this may apply to other language as well.