This is 14k Yellow or White Gold Push Back Earring Butterfly Backing. This push backs will make your earrings secure. The price are available by piece and pair. We have a few variations of these backs: small, medium, large and extra large: 

        - Small are measures 3 x 3.8 mm.

        - Medium are measures 4 x 4 mm.

-       Large are measures 5.5 x 4.5 mm.

        - Extra Large are measures 5.5 x 6.7 mm.

For any question please contact us at our store noahsjewelry