Original 1936-37 General Motors Customer Research Information Sales Set. The original envelope holds a Buyer's Guide Booklet, The Philosophy of Customer Research Booklet, The Story of Knee Action Suspension Booklet, Your Car As You Would Build It Booklet, and an addressed Business Reply envelope. The original holding envelope shows some wear and blemishing while the booklets are in very good condition [see photos]. Very rare and informative GM Sales Set that will display well.