The X400 is powered by two 3-volt 123A lithium batteries, which are included. The X400 has a runtime of 2.4 hours of tactical-level white light on a set of batteries. For purposes of comparison, a 6-volt SureFire light with the 120-lumen P61 incandescent lamp assembly has a runtime of 20 minutes.
The light is built to military specifications. It features a precision-milled aerospace-grade T6-AL aluminum body with a Mil-Spec Type III hard-anodized black finish. The rails and rail adapter, machined from the same aluminum, are a nice upgrade to the X300. The X400 is O-ring and gasket sealed, making it waterproof to a depth of 66 feet.
The X400 measures 3.54 inches long by 1.56 inches wide by 1.86 inches high (with standard switch) and has a 1.06 diameter bezel. Its total weight (with batteries) is 4.4 ounces or less than a loaded pistol magazine.Switching options
SureFire's new offering features digital current regulation to maintain a consistent light output throughout the useable life of the batteries. The X400 also has a modular switching system with several switching options available.
This tactical light comes with an ambidextrous toggle/momentary pressure switch that provides momentary and constant-on activation. For constant-on operation, press the switch up or down. For momentary activation, push the switch forward. It's easily operated with the trigger finger in an indexed position (Uniform Cover Position) or with the thumb of the support hand. Momentary operation of the X400 requires the shooter to use his support hand when firing unless a remote pressure switch is employed.
Weapon-specific Dev Group (DG) remote switches for a variety of popular service pistols are available from SureFire for the X400. The DG Remote Tailcap Switch enables light activation with a center-mounted pressure pad on the handgrip's front strap. This gives the user precise control without altering his weapon grip.
SureFire is also developing different switching options for use on shoulder arms. The waterproof XT-07 Rail Mount Tape Switch is an example. The XT-07 includes a disable feature, constant click on/off push button, and a momentary-on tape switch attached via a 7-inch cable connected to a replacement tailcap. Simply pop off the standard rocker switch tailcap and pop on the XT07. The tape and rocker switches are integrated onto a molded urethane brace that is flexible enough to snap onto a Picatinny rail. The constant-on push-button switch and momentary tape switch operate independently.
The X400 is designed to fit the Picatinny rail and the Universal Standard rail. The X400 mounts on the weapon using a Nylok screw clamp mount. It's a very solid mount that provides excellent boresight repeatability, and although it sacrifices the quick detach and quick installation of a lever latch, it takes little time to install and remove. The X400 includes interchangeable spacer blocks for Universal and Picatinny rails because Universal and Picatinny rails have different specifications and require different adapters for a proper fit.
The X400 provides a superb light and laser for long guns when employed with the XT-07 removable tape switch module for the X-Series. The X400 is especially suited for use on compact assault rifles, PDWs, SMGs and pistol-caliber carbines. The integrated system eliminates the "module stack up" that would be the case where a separate laser sight and illuminator are employed.
The era of LED lighting is upon us. Australia has banned the sale of incandescent bulbs after 2010. The U.S. Department of Energy predicts affordable, efficient LED lamps will be lighting everyone's homes by 2025. Cities around the globe have already saved millions by replacing fluorescent and incandescent lights with state-of-the-art LEDs. And now SureFire has revolutionized law enforcement tactical lighting by producing a flashlight that combines a targeting laser with a high-output LED.
Eugene Nielsen is a private consultant. The former police officer can be reached at firstname.lastname@example.org.