Inserter/extractors work by leverage; when the lever is pushed or pulled, the extractor pivots on the roll pin and the “head” portion pushes against the cold wall or sheet wall channel to engage or disengage the PCB. Depending on the design, different models may be capable of aiding in both the insertion and extraction of the PCB, or extraction only; those that have “U” shaped head such as the one shown on this slide, can insert as well as extract. All extractors connect to the PCB via a roll pin, this is the point on which they pivot. All extractors have the option to have the pin pre-started, denoted by a “P” prefix in the part number. A pre-started pin will allow for a faster and easier installation of the extractor to the PCB and minimize chances of losing loose assembly pins. As shown, some models offer a latch for positive locking to prevent board walk-out. Those that include a latch will have two pins; one for the pivot point, and one for the latch.