Use of the final production building in J. Wiss & Sons Co's modernization and expansion program will be inaugurated at a Christmas luncheon party for some 700 employees and guests Wednesday.

The new two-story structure covering 25,000 square feet, will house the 119-year-old cutlery firm's grinding and heat treating operations.

The main plant at 33 Littleton Avenue underwent extensive renovating and face-lifting in the early part of the program. A remaining project is a new office building which will be started early next year. The whole undertaking is within the Fairmount Urban Renewal Area.