The clasp envelope is made of microfiber craft paper; Environmental glue is painted on the envelope closure; The clasp adopts antirust tough metal clasp; automatic riveting; Both the clasp and glue can seal the envelope to protect the things inside; The metal button of the clasp can be used repeatedly; the paper is 100% recyclable; Envelope size: Min.: 70mm*100mm; Max.: 300mm*460mm. The size of the envelope can be customized according to your need; the color of the clasp depends on your choice; It can be applied in the preservation of files, pictures and books, the package of goods delivery and the collection of important items.