The Mk4 Battle Light provides 500 lumens of white-light illumination, along with an adjustable low-profile design. The light uses a slim Picatinny-rail attachment point that wraps around the light body, allowing the light to be installed tight to a rifle's rail. The attachment is secured through the use of a thumb screw.
This design works to virtually eliminate barrel shadow, giving users a clearer, unobscured view of their targets before engagement. The design also helps shooters engage the switch easily, ensuring smooth, trouble-free operation.
The light body is made from 6061-T6 aircraft aluminum, which features a mil-spec hardcoat anodized finish. The body measures 1 inch in diameter and features a length of 5.98 inches. The total weight of the unit is 4.9 ounces. The light runs off a white-light LED with a beam divergence of 10 degrees and a maximum range of 330 yards. The light is waterproof to a depth of 16.4 feet.
The Mk4 runs on two CR123 batteries or a single rechargeable lithium-ion battery, which is sold separately. The battery life measures anywhere from 1.25 to 1.75 hours, depending on usage.
The light features a pressure-sensitive pad on the tailcap of the unit that allows the user to depress slightly for momentary on operation or depress fully for constant-on. The Mk4 is also supplied with a remote cable pressure pad that allows users to operate the light from a comfortable point on a firearm's rail.
The Picatinny-rail adapter is fully ambidextrous and can be flipped using two screws in order to accommodate right- or left-handed shooters. The light also features a rotating tailcap that allows owners to orient the pressure-pad cable according to user preference.
The suggested retail price on the Steiner Mk4 Battle Light is $329.