Abstract: A fastening device is disclosed for releasably securing together a plurality of sheet or plate members assembled in face-to-face or back-to-back contact, the sheet or plate members being provided with correspondingly positioned, shaped and dimensioned registration apertures. The fastener comprises first and second fastening portions spaced apart along an elongate flexible connector element, such fastening portions being positionable from opposite sides of the assembly of sheet or plate members with the connector element extending over an edge of the assembly, said fastening portions being releasably interconnectable, with a spigot element of one of them projecting through and engaging in the aligned apertures to inhibit relative movement of the sheet or plate members.There is also disclosed a method of releasably securing together a plurality of printing plates having registration apertures using a fastening element passing through a set of aligned apertures.