15 Sets Brass (Nickel Free) Ring-Spring Snap Fastener Button "F3" 17mm, Finish: Brass-Glossy (Gold-Coloured), Strenght: Light Ring-Spring Snap Fasteners 17mm (System F3) Material: Brass (nickel free) Finish: Brass-Glossy (gold-coloured) Range of use: strong fabrics, leather goods Strength of Fastener: light (bracelets, light leather wear)