This is the whole hook cover piece with the needle plate and the bobbin cover plate. The Cover Plate, which is part #4123077-02 (Pop-Out), you can no longer purchase alone. You have to purchase the whole kit to get this part.

Guaranteed to fit Husqvarna Viking Sewing Machine Models:
200, 205, 210, 215, 225, 230, 234, 250, 300, 305, 310, 315, 320, 325, 330, 335, 340, 340D, 341, 341D, 350, 360, Prelude 370