Mind you: this is a second-hand product! It is in excellent condition though.

Liven up any PLANESCAPE or AD&D campaign with the MOSNTROUS COMPENDIUM Appendix III, which features 128 pages of monsters that lurk on the Inner Planes, the Astral Plane, and the Ethereal Plane - some of the strangest and most inhospitable environments in the multiverse. Most of the critters are brand new, though a few old favorites have been updated. This book also provides a detailed look at the ecology of the planes in question, not to mention an appendix of inner-planar creatures that're more like animals than monsters. And, of course, all-new illustrations vividly bring each of these exotic beings to life.