This is a 44-page supplement from Mike Stewart.
Now this is a fun one! Meant to be reminiscent of the old mail order catalogs of the time, this book takes its name from two of the premiere heroic NPCs of the core book. The book is full of fantastical and mundane items characters can buy, find or engineer themselves. And it is a full book.
Vital statistics are given including any bonuses it provides or damage it does (or can take) and the equally important availability (%) and price in British Pounds and American Dollars.
This is also a good book for any Victorian era game with a Steam-Punk lean to it. It makes a nice companion piece to Cubicle 7's Victoriana - Faulkner's Millinery and Miscellanea. My only complaint here is Troll Lords really missed out on the chance to make this look like a Vicotrian era catalog, complete with vintage art. I know they were trying to maintain trade dress with the line and readability, but it would have been a lot of fun.
Buy this if you REALLY want to know how much the Nautalis would run you in Pounds Sterling.