Hello All, a short introduction: I work in Russian company which manufacture cars. It is small company and now we have only one car. During developing this car we learn on our mistake. At present we develop engineering instruction "part number". we have our system of part number for component which we design. but we can not decide what number need for purchase component. I have experience of work in european aerospace company. when i designed something for aircraft and I used purchase component, I did not give number for it component. I would like to know your point of view and want to know experience world automative industry. Thanks for your help.