Sean's Flashlight Site

SureFire L4 Digital Lumamax:
Produced by Surefire

This is the new style body for the L4.  Instead of three flat sides on the body, there are two rounded sides.

The Surefire L4 is a Digitally-Controlled 5 watt LED flashlight.  It uses digital current regulation circuitry
to achieve a constant level of brightness for the useable life of the batteries.  The L4 also comes with a
click on/click-off lockout tailcap switch.  To lock out the tailcap switch,
just unscrew the tailcap one half turn from the fully tightened position.
 
 

The L4 runs on 2 CR123 lithium batteries for an average of 65 minutes and has an average brightness output of 65 lumens.
After ~65 minutes, brightness will drop off sharply, giving you decreasing brightness over the next 25 or so minutes.
After that, the light output will be very low, but still useful enough to find your way back to more batteries.

This is the run-time of the KL4 head running from 1 Duracell DL123A battery
This shows 3 hours and 30 minutes of diminishing brightness.  After the initial drop
during the first two minutes, the KL4 holds at about 30 lumens for over 90
minutes and then drops off slowly for several hours.
The blue line shows the run-time of the E1L (KL1 head) on one cell.

 

On the left is the Surefire L4, notice the square shaped LED die surrounded by a custom "orange peel" reflector.
On the right is the Surefire A2 with 3 embedded 5mm LEDS and an incandescent lamp in the middle.
 

Here is a size comparison between the Surefire L4, A2, Brinkmann Legend LX, Mini-Mag 2AA and Arc LSH.
Below are some beamshots comparing some of these lights.

Beamshots:

Here are some outdoor comparison shots:

 
 

Here are some indoor comparison shots:

 

These shots are at about ~45 feet.