Laser Cannon (Spartan Laser)

The Weapon/Anti-Vehicle Model 6 Grindell/Galilean Nonlinear Rifle[1] (abbreviated W/AV M6 G/GNR), also known as the Spartan Laser, is the UNSC's ground-based, man-portable, anti-vehicle, directed energy weapon. It is the only known battery-powered UNSC weapon, and is the most powerful infantry weapon fielded by UNSC forces. It is capable of penetrating multiple targets, including tanks, unlike the Sniper Rifle, which can only penetrate infantry. It is alternatively known as the Galilean, or, in player lexicon, the "Splaser".

Pictures
http://images2.wikia.nocookie.net/halo/images/thumb/e/e6/M6_Spartan_Laser.jpg/300px-M6_Spartan_Laser.jpg