The 849-5-9 part of Winchester is an internal, proprietary part code provided to the customer. It is used to accurately identify a particular part, such as a stock or trigger assembly, for ordering purposes. The code consists of four numbers, separated by a dash and occasionally further divided into individual numbers, such as 849-5-9. In the Winchester 849-5-9 example, the 849 is the model number, 5 denotes the finish, and the 9 is an identifying number for a particular part in the model.