Patent ID: 7631984

Claim:
A flashlight, comprising: a switch assembly; a body including a first end and a second, wherein the switch assembly is disposed within the body at the second end, further wherein the body is adapted to receive a first number of batteries therein, the first number of batteries being at least one; an extension unit securable to the body at the first end, the extension unit adapted to receive at least one battery therein, thereby providing the flashlight with a second number of batteries, the second number of batteries being at least one greater than the first number of batteries; and a flashlight head assembly securable to the body at the first end or to the extension unit, the flashlight head assembly comprising an LED and an LED driver circuit adapted to deliver a predetermined current through the LED from either the first number of batteries or the second number of batteries, wherein, when the flashlight head assembly is secured to the body at the first end, the first number of batteries applies a first voltage to the LED driver circuit such that the LED driver circuit delivers the predetermined current through the LED and the LED operates at a first output level, further wherein, when the flashlight head assembly is secured to the extension unit, the second number of batteries applies a second voltage to the LED driver circuit such that the LED driver circuit delivers the predetermined current through the LED and the LED operates at a second output level.