By default in probid even if the mod rewrite is enabled, the links looks not the bes as it could, for example users store url is looking like this:
None of a store owner will like to have any extra words, numbers in his store url so this mod will help you clear the urls and allow them to be as most friendly as it can to be, lets take an example if user has store which name is "MODS4U MODIFICATIONS FOR PROBID"
New url will look like this:
Your users will love it. And thats not all this mod also improoves the urls for listed auctions, categories and subcategories.