After the screw wire termination, the second most commonly used method is a spring style connection. As with screw styles, there are also multiple types of springs that can be used. One very common style of spring wire termination is shown here and includes an actuator (or lever) mechanism for opening the spring apart and an internal leg or leaf spring contact. Terminal blocks using leg spring technologies are actuated with a finger or screwdriver depressing on an orange lever. The lever is used to open the spring so that a wire may be inserted. First depress and hold the lever down, insert a conductor into the wire entry area and release the lever. An internal spring retains the wire in the housing. To remove a wire, simply depress the lever again and remove the wire. Other versions of spring connections exist, some require no tool for wire insertion at all and are called “poke-in”, while other versions require the use of a tool (typically a screw driver) which is inserted into the terminal block itself for opening the spring, without the use of an integrated lever.