This got me about $30 off a 1 week prepaid rental in Europe - the biggest discount I was able to get after trying multiple codes. I gave the quote to a well-known car rental broker that promises to beat all competitors' prices, and they gladly gave me this price for the exact same Avis rental, plus a few additional dollars off. The nice thing is that Avis charges a $50 fee for prepaid rental cancellations (at least in this particular country; not sure about elsewhere in Europe or the world), whereas the broker charges no cancellation fee.