Description from Suntup Website

The limited edition of Stranger in a Strange Land by Robert A. Heinlein is presented in three states: Lettered, Numbered and Artist editions. The editions measure 6” x 9” and feature eleven full color illustrations by Thomas Canty. All editions are signed by Thomas Canty. The text is the complete, uncut version.

The Numbered edition of 250 copies is a quarter cloth binding with custom designed letterpress printed sides, and a foil stamped spine label. Endsheets are Hahnemühle Bugra, and the edition is printed offset on Mohawk Via. The slipcase enclosure is covered in a two-toned cloth, and the edition is signed by artist Thomas Canty.

Only the Artist Edition of Starship Troopers and Stranger in a strange Land could be bought seperately. The numbered and lettered edition had to be bought as a set.

Also check the other states of the book:

Artist Edition - Lettered

The other book in the set:

Starship Troopers