A Door Closer is basically a mechanical device meant for closing a door once it is opened. They are usually metallic and also protect forceful banging of the door. They are suitable for all types of doors. Door closers can be installed both on the interior and exterior doors. They usually work on a spring action that pulls the door.
Materials Used

Door closers are usually made of metals like:

• Iron
• Aluminium
• Steel
• Brass

Styles of Door Closer
Door closers usually have two styles:

• Manual Door Closer: A manual door closer usually closes the door after it is opened by hand. In order to restrict the speed of the door, most door closers have a hydraulic damper. The speed of the door can also be adjusted by fixing two set of screws adjacent to hinge end of the door closer. Again there is a spring type door closer that is used on a swing door.
  
  
• Automatic Door Closer: They are also known as door opener and opens the door automatically, typically under the control of a motion detector, push button or other device and then closes it as well. These closers usually employ a motion or proximity detector to evaluate when it is the right time to close the door.

Finishes

Door closers are available in variety of finishes to protect them from corrosion and also to enhance their look. The finish also act as decorative and should match with the design & style of the door. Antique finish, black iron finish, satin chrome finish, polished brass finish and brushed nickel finishes are very common among door closers.