Microprocessor regulation and six levels of output
available on demand to meet any task. High-output or long
runtime: now you can have both in one rugged LED flashlight.
Constructed of aerospace grade aluminum with a rugged
military specification hard-anodized finish, and powered by two
lithium batteries (10-year shelf life), the U2 Ultra features a
five-watt LED (Light Emitting Diode) and the extended runtime
typical of LED flashlights. The U2 features a body-mounted
selector ring that allows the user to choose one of six output
levels: from a battery saving two lumens of light—perfect for
finding your keys in the dark—to a retina-searing 80 lumens at
its highest setting. The U2 is equipped with a
click-on/click-off tailcap pushbutton switch that gives the user
the option of momentary activation (for self-defense use or
emergency signaling) or the convenience of a constant-on
“click” switch. The U2 also features microprocessor
regulation circuitry to match the LED's current requirements
with the battery's output to maintain a more consistent level of
light output for the useable life of the batteries (as opposed
to unregulated lights, which are subject to a steady decline in
light intensity beginning shortly after activation).
The U2 produces over 40 hours of useful light on the lowest
setting. Unlike most LED flashlight manufacturers -- who inflate
the light output and usable runtimes of their LEDs -- SureFire
provides realistic output and runtime specifications based on
scientifically obtained measurements. Although any LED --
including those produced by SureFire -- can continue to produce
negligible light output for over 100 hours, the amount of useful
light produced is of a shorter duration.
