A 1943 Salesman's data book
Not sure on this one i can't find any info on it but it is a very interesting piece of American History.
This book showed the salesman info on if you give a discount by how much you need to increase the order to off set the discount.
A checklist for the salesman,tax deductions, Legal points, unit cost they sold in Doz. Facts about different cities to probably strike up a conversation.
A very neat little book it is 4 1/2" long by 3" wide 1/2" thick.
(View pic's for condition will take more pic's upon request)