This book features Allis-Chalmers, Deutz, Deutz-Allis, Fahr, La Crosse, Monarch, Rumely, Simplicity, and Venduvre. All of these companies were related in the past and to help preserve their history through farm toy collections they are featured in this book. Farm toy collecting is a major hobby and Crilley spent years himself collecting and composing books to help fellow collectors.