SII-TKU Mark 19 Plasma Rifle

 SII-TKU Mark 19 Plasma Rifle with a 5 gauge (24.8 mm bore) Grenade launcher and Chain Sword attachment is the standard infantry weapon of choice for the United Stars Marine Corps in 4937 OTT.

 It was a relatively old system and was with the Corps for over 150 years since the introduction of the Mark 1 in 4780 OTT, and the Mark 19 still looked more or less like the old Mark 1 with only minor improvements or changes.