This set includes two books from Dar Corporation, part V from 2003 and part II from 2004. The books cover the design of aircraft and are a great addition to any aviation enthusiast's collection. Made in the United States, these books are a valuable resource for anyone interested in the history of aircraft design. The California Prop 65 Warning does not apply to this item. Preliminary Confirmation Design & Integration Of the Propulsion System. Component Weight Estimation.