A flashlight having features that align the light source of a lamp with the principal axis of a reflector, such flashlight having a head assembly that includes a reflector and a lens. The reflector has a central opening that surrounds the principal axis of the reflector. The light source of the flashlight is held by a lamp base and an axis of the lamp base is aligned with the light source. Particularly, the hottest portion of the light source may be aligned with the lamp base axis. The self-centering characteristic of the lamp base is configured with a non-cylindrical feature to be seated in a base receiver. The base receiver includes a receiver axis that is aligned with the principal axis of the reflector. The lamp can include a pair of electrodes and a filament light source extending between the electrodes.