UNOde50 HEART NECKLACE UNOde50 jewelry is designed in Madrid and crafted by artisans in Spain using traditional methods that go back centuries. Hypoallergenic Lobster claw clasp Adjustable 18" to 20" in Length Nickle -free This UNOde50 HEART NECKLACE, sterling silver-plated, is made of leather and features a heart-shaped centerpiece inspired by the iconic UNOde50 nail. It has a lobster claw clasp that allows the piece to be adjusted to the desired size. Nickel-Free. Hypoallergenic.