They are textile metal accessories, those are consisting of four parts and fastened two parts on each side of the fabric, leather or textile for the purpose of two sides connection. They can be used on shirts, coats, shoes, wallets, trousers, coats, dresses, T-shirts, hobby products, linens, home textiles, etc. for the purpose of connection. There are two sorts of snap fasteners; one of them can be sewed on the garment and consists of two parts and the others should be fastened by using pressure by proper tool and the machines. Those are prong snap fasteners, S-Spring snap fasteners, Ring spring snap fasteners. You can buy those snap fasteners from klinkshop.com web page according to your request as kits with easy to use tools or spare packs if you already have bought tools and machines before.