Abstract: A night vision device with a modular assembly includes an image intensifier module or assembly, which includes an image intensifier tube and a power supply. The image intensifier tube receives low-level light from a scene too dark to be viewed with the unaided eye, and provides a visible representative image of the scene in phosphor yellow/green light. The power supply receives low-voltage power from a source, such as a battery, and provides power at voltages appropriate for operation of the image intensifier tube. The module includes a separable high-voltage connector for electrically connecting the power supply to the image intensifier tube. According to a preferred embodiment of the invention, the connector includes structure for physically connecting the power supply and image intensifier tube in separable nested relationship while also providing environmental protection to electrical connector features of the module.