An enhanced, push-button multi-battery housing with digital circuitry offering up to 75 hours run time, plus a more than 35% weight drop versus traditional housings. The patented NL914C Power Pack by Nightline, Inc.™ takes the PVS-14 night vision monocular to the next level by rethinking the entire battery housing. Its unique layout allows the use of shorter but more powerful CR123A lithium batteries in the same tray as the AA battery. The user can choose to use CR123A or AA batteries as desired. Plus, the design offers significant weight savings: the NL914C Power Pack weighs only 1.6 oz / 45 g total, or approximately 36% less than a traditional single-AA battery housing (which weighs 2.5 oz / 71 g). If the goal is to relieve the strain on your neck and make it easier for you to focus on the task at hand, this product delivers. – Finally, the #1 failure point on milspec PVS-14 housings are the rotary dials for power and gain control. These relatively fragile dials are completely replaced by push buttons on the NL914C Power Pack, leading to much better long-term durability and vastly improved water resistance. There is no maintenance required, and the controls are easy to press and very intuitive. Simply click the power button once to turn the monocular off or on, press and hold the + or – button to change gain, and click the IR button to momentarily activate the built-in infrared illuminator or double click it for constant on.