Linx Paved Heart Clasp Snake Chain bracelet extender in 925 sterling silver. 
Linx extenders are universal, meaning they are compatible with not only your favorite Linx bracelet, but also standard size charm bracelets of other brands as well. 
Bracelets extenders are the perfect solution for charm bracelets that fit a bit tight. 
Diameter is 3mm. Extenders adds an 3.5cm (1.3in) in length. Multiples may also be added for additional length.