The Essentials package, offered at a discounted price, combines the first nine Gonstead Chiropractic Books into a single digital text to provide the chiropractic student and practicing doctor with all of the fundamental detail explaining the biomechanical basis for the Gonstead Chiropractic technique, including detailed descriptions for the diagnostic tools to establish the primary subluxations, compensations, and vertebral and pelvic listings to help the reader to achieve the most specific and accurate adjustments.