A device for influencing an electron beam, especially a deflector unit for an electron beam lithography machine, comprises a plurality of coil formers each with a bore defining a passage for the beam and each carrying coils operable to generate magnetic fields for deflecting the path of the beam when passing through the passage. The base has a floor and walls to store and to release water, and straps to secure temporarily a pet such as a dog. Furthermore, compound scopes are recognized and stored such that an index of complex search scopes is provided to eliminate rehashing of the searches based on these complex search scopes. An end of the housing is closed to abut against an end of the cover, and an opposite end of the housing is partially opened to receive an opposite end of the cover. They may also provide for a secure platform to validate the strength of the information, such as a PIN or password, prior to further processing of the sensitive information.