Some airlines call them restricted tickets, and this may be closer to the truth.

On overseas travel, charges for changing a restricted ticket have been in effect for 10 years or more.

USAir has somewhat liberalized its policies on the restricted ticket.

In recent months, however, several airlines have changed their policies on their most heavily restricted tickets.

The lowest price is for a restricted ticket requiring a round-trip purchase; the higher fare carries no limits.

The round trip air fare is about $160 to $325 for a restricted ticket; an unrestricted ticket is $326 and up.

For the trip back, travelers would buy a restricted - but discounted - ticket.

After 24 hours of purchase, restricted tickets are almost never refundable.

Sabena was offering a restricted ticket for a round trip to Brussels for $904, which qualified as the best price on that route.

The fully refundable fare is $50 more than a restricted ticket and you're not certain of your return date?