Abstract: An underwater flashlight has an adjustable focusing beam and a waterproof battery pack which can be removably changed underwater. The flashlight includes a watertight housing having a slidably mounted lamp therein slidable by an external sliding focus member having a permanent magnet mounted therein. The permanent magnet moves an internal sliding focusing member also having a magnet therein coacting with the external magnet. The slidable inside focusing member is connected by a link to the lamp for moving the lamp into and out of a reflector when focusing the lamp. An on/off switch is attached to the slidable outside focusing member and has a magnet mounted therein for actuating a pickup coil attached to the slidable inside focusing member. The flashlight includes a waterproof attachable battery pack which has a magnetic switch therein actuated by a magnet in the watertight housing of the flashlight so that the batteries do not provide an electrical connection until the contacts are brought together.

Abstract: An underwater flashlight has an adjustable focusing beam and a waterproof battery pack which can be removably changed underwater. The flashlight includes a watertight housing having a slidably mounted lamp therein slidable by an external sliding focus member having a permanent magnet mounted therein. The permanent magnet moves an internal sliding focusing member also having a magnet therein coacting with the external magnet. The slidable inside focusing member is connected by a link to the lamp for moving the lamp into and out of a reflector when focusing the lamp. An on/off switch is attached to the slidable outside focusing member and has a magnet mounted therein for actuating a pickup coil attached to the slidable inside focusing member. The flashlight includes a waterproof attachable battery pack which has a magnetic switch therein actuated by a magnet in the watertight housing of the flashlight so that the batteries do not provide an electrical connection until the contacts are brought together.