Staple guns are used for many different applications and to affix a variety of materials, including insulation, house wrap, roofing, wiring, carpeting, upholstery, and hobby and craft materials.Unlike office staplers, some staple guns lack an anvil, the metal plate with curved slots that office staplers use to bend the legs of the staple inwards or outwards and flatten them against the paper.For example, a post stapler can be used to join the bottom flaps of a corrugated box but a blind clincher is used for closing the top of a closed box where post anvils are not possible.In the office stapler, by contrast, the staple can be driven directly by the user's muscle power, at a relatively slow speed, because the paper is firmly supported by the anvil.In other words, the staple gun substitutes the workpiece's inertia for the missing anvil.