>Well, the value (or ControlSource) is an Integer. The format and mask just display it with the colon in between
>So, if you want an hour you would enter 100. For one second enter 1
>
>How would the textbox know that 1 is either one second or one hour ?

I'm not sure, but in my opinion it's inconvenient. I'd rather try with the classes Marcia suggested if I can get ahold of the article...