This simplebeads unlimited hook fasteningis used with leather or cord to attach necklace ends together this is a great way to securely fastening jewellery adding a unique touch to your personalised jewellery designs secure the ends of the cord with a flat or round crimp and then attach the hook a jump or split ring will be needed for the other endthere are 25 hooks included in the pack all measuring 18 x 6 mmsize 18 x 6 mm25 packcolour nickel plateduse with leather or cordbeads unlimi