SOUFEEL 925 Sterling Silver Heart Core Sky Blue Murano Glass Bead Fit European Bracelet SOUFEEL products are genuine S925 Sterling Silver. The material of the item consists of 92.5% silver combined with other metals; 100% safe for sensitive skin. Most items are in stock in US Local Warehouse. SOUFEEL charms' hole size is between 4.2mm-5.5mm. Most charms and beads are compatible with most U.S. and European bracelets and necklaces. SOUFEEL products have no screw threads inside, including both ends of Soufeel bracelets. Soufeel charms and beads fit non-threaded bracelets or chains. SOUFEEL ships all products by themselves and some also fulfilled by Amazon. The delivery time is within 5-14 days by sellers and much faster by Amazon. SOUFEEL customer service is very prompt. Amazon allows us reply customers' messages within 24 hours but we always solve customer's inquiries within 8 hours. Maybe you can receive a solution in the next minute after sending the message.