Standard issue weapon of the Olympian Army. Relies on a roller-delayed blowback system. Designed around durability and reliability, it fires a 7.62x39mm cartridge. Although it fires slower, has a shorter effective range, and is less accurate than the K-18, it is more reliable than the K-18 and is much cheaper. The controls, while not ambidexterous, are large and easy to use. The charging handle doubles as the dust cover. In addition, while the 7.62mm round is slower than the 5.56mm round used in the K-18, it carries far more energy and gives the Model 155 a reputation for stopping power. It is exceptionally effective against body armor. It is fitted with an Olympian Army bayonet based off of a fighting knife.