These are very tiny earrings and may not work for a main piercing unless you have small earlobes. Because of the balls, the space for the earlobe is smaller than 10mm. (See photo) For their small size, they are weighty and seem to be strong. The only reason I do not give 5 stars is that one of my pair came without a pin to hold the wire in and I had to take them straight to a jeweler for repair, adding to my cost.