To provide an assembly capable of securely and detachably fixing an auxiliary frame to a main frame.

Disclosed is the assembly capable of a couple of attaching and detaching auxiliary lenses 10 to and from a couple of main spectacles, the assembly being characterized in that the main spectacle frame is equipped with a couple of projections 15 and 16 having recesses or openings for receiving projections 15 and 16 provided on the auxiliary frame 8 holding the auxiliary lenses 10. With this structure, the projections 15 and 16 on the auxiliary frame 8 can securely be fitted in the recesses formed in corresponding projections on the main spectacle frames.