Be the coolest guy at the field! This is brand new and has tamiya connector. This is Tachyon V2 More than just a simple ammo Core features AMMO COUNTER Counting how much ammo you have left is Tachyon's primary function. Your ammunition status is displayed both as an exact number, and also as a graphical progress bar to provide readout when your eye is not in direct focus on the screen. Tachyon provides a capability to save up to 6 ammo count presets and makes it easy for you even if you use multiple magazines with different capacity. These presets can be modified and applied with a press of a few buttons anytime in the field. Additionally, Tachyon will alert you when you reach 2/3 and 1/3 of your magazine capacity by changing the color of the ammo count readout. This way, you will always notice when your magazine is almost empty. BATTERY MONITOR Since Tachyon is powered directly by your weapon's battery. besides you ammo status, it also provides another vital piece of information: your weapon's battery status. Tachyon features a high-accuracy measurement algorithm for both Ni-MH and LiPo batteries, in multiple voltage configurations (7.4, 8.4, 9.6 and 11.1 volts) Using a GBBR or HPA? No problem! Tachyon can also be powered by an external battery, such as a 9-volt cell. REAL TIME CLOCK To help you keep track of time, Tachyon also features an integrated real time clock. FULLY CUSTOMIZABLE I believe that when you buy something, you should be able to do anything you want with it. Using the on-board color editor, you can select any custom colors for the user interface, display backlight, and ammo count threshold colors. Customize the color scheme to match your favourite sci-fi shooter game! If you have experience in programming Arduino or AVR Microcontrollers, you can download Tachyon's open-source firmware to fully customize every single aspect of your device! ADJUSTABLE BRIGHTNESS No matter if you're fighting at day or night, you can quickly adjust the screen brightness directly from the home screen at any time. HIGHLY COMPATIBLE Tachyon mounts on any 21-22mm weapon accessory rail in any orientation, and has a very low profile of just 26.5 mm (1.05") to ensure that optics can be mounted in front of the device without blocking your line of sight. The required barrel sensor uses a mechanical clamp instead of a thread. This ensures compatibility with a wider range of barrel diameters and also provides the ability mount on non-threaded barrels. Does Tachyon block your sights anyway? Don't worry, with the ability to rotate its screen picture, Tachyon can be mounted on the side, and even upside down! (Why would anyone do that though?) RESILIENT Tachyon and its Infrared barrel sensor are made out of Laser-printed Carbon-black Nylon-12, which provides excellent mechanical capabilities and impact resistance. To protect its display, Tachyon also comes with an optional acrylic screen protector (not shown in the picture) How does it work? Tachyon works by detecting your outgoing shots using a custom barrel-mounted sensor. Setup is easy and simple. All you need to do, is to attach the barrel sensor, and the Tachyon computer to your weapon. Then, you use the included battery splitter cable to connect the device to your weapon's battery (No soldering or re-wiring required). If you have more questions, please see my FAQ