A pad of plastic bags comprising a plurality of bag units, each comprising a bag-forming pocket and a selvage portion, the pockets having front and rear walls and sealed edges and the selvage portions being integral with the pockets and also having front and rear walls, the selvage portions being connected...http://www.google.es/patents/US4557384?utm_source=gb-gplus-sharePatente US4557384 - Pad of plastic bags
