The dermis has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures. It is made up of a thin upper layer called the papillary dermis, and a thick lower layer called the reticular dermis. Epidermis. The outer layer of the two main layers of the skin.
A fastener is a hardware device that mechanically joins or affixes two or more objects together. Fasteners can also be used to close a container such as a bag, a box, or an envelope; or they may involve keeping together the sides of an opening of flexible material, attaching a lid to a container, etc. There are also special-purpose closing devices, e.g. a bread clip.
For the Transformer, see Railspike. A rail fastening system is a means of fixing rails to railroad ties (United States) or sleepers (international). The terms rail anchors, tie plates, chairs and track fasteners are used to refer to parts or all of a rail fastening system.