The diameter of the charm's hole is about: 4.5 to 5.0 mm. It is compatible with Pandora bracelets, U.S. bracelets, European bracelets, and most kinds of charms bracelets but Pandora Me. Charm's Hole size is around 4.5 mm-5.0 mm in diameter. The charm is made of copper, suitable for daily wear as body jewelry. We suggest you remove the charm while bathing, swimming, or exercising. Best gifts for mom, mum, daughter, wife, aunt, sister, grandmom, stepmother, friends, best friends, BFF, family and women. The great present for any occasion, such as Christmas, Birthday, Mother's Day, Anniversary, Valentine's Day, New Year, or any special day for you or your friends and family. Nice gift for birthdays, Mother’s Day, Valentine's Day, Christmas, anniversaries, Memorial Day, New Year's Day, Easter, and your special days. Suitable for mom, mother, mum, wife, grandma, grandmother, auntie, aunt, best friends, family, and women.