This page will return the 1x2 or 2x1 call signs which are valid amateur radio call signs but which are not found in the FCC's ULS database. Since they don't even show up in the FCC's database they have been canceled/expired for well over the two year required wait for cancelled/expired calls and are therefore immediately available for submission on a vanity license. As always, before filing for a call sign you should check to make sure that someone else hasn't already filed an application for the desired call sign. Also, many of the 2x1 call signs are region restricted, meaning that they cannot be applied for unless you have a postal address that is within the geographic region for that call. Please see the FCC's instructions relating to this, which can be seen by clicking here. Selecting the 2x1 All Region calls will include all of the 2x1 calls regardless of region restriction. Selecting the 2x1 Minus Restricted will return all of the 2x1 call signs without the restricted regions being included.