Ace [A-6; 1st printing] 1965 paperback. Cover and title-page illustration by Jack Gaughan, 444 pages ,75 cent cover price. Condition is Good+ to VG-: tight with very mild tilt, spine is slightly dished and several faint lines down middle, age tanning is mild to moderate and uniform (slightly darker on insides of covers, as expected for this vintage.) No stamps, marks, or writing - a clean copy.
For other books by a different author, the condition I list might not seem so great, but given the popularity of this series and the fact that the Ace set had no 2nd printing - you will have difficulty finding any copies at all.

The third book of "THE LORD OF THE RINGS" trilogy by J. R. R. Tolkien - in the super-rare Ace "pirate" true first-paperback printing. The original editions came out in Britain in 1954 and 1955, but there was no paperback edition until this one. The reason why the Ballantine editions carry the the statement that they were the only authorized editions is that Ace Books took advantage of a loophole in the copyright law and printed an American paperback edition without paying royalties to the author. (Though they later paid, after the public-relations damage had been done.) Each book states "complete and unabridged" on credits page - but has no date or copyright info. The series as a whole won the International Fantasy Award in 1957. This is one of the all-time best works of fantasy, making my top-20 list for sure, and I've read the series about a dozen times. Given how famous the trilogy is, I'm leaving off my usual plot summariy. If you are interested in this - you've already read the book. Most sources give the dates for the trilogy set as 1965 (beginning of year), but one source (Spelman's compilation of SF&F published by Ace) lists them as 1964. Jack Gaughan provided a decent set of covers for all 3 - capturing the spirit nicely.