Developed at the tail end of World War One, the Pedersen Device was a drop-in conversion unit for the 1903 Mark 1 Rifle, which would let an infantryman switch between a full power bolt action rifle and a semi-automatic pistol caliber carbine as needed. While a novel and promising concept, the end of the war stopped development short, and most of the Devices and their accessories were destroyed. This grouping of Pedersen accoutrements consists of a belt case, a canvas pouch, magazine carrier, two tools and a box of ammunition. The case is blackened stamped steel, with a hinged lid and a brass belt hanger. The pouch is tan canvas, with no maker's marks and four grommeted vent holes in the rear. Both tools are blued steel with no visible markings, and the magazine is marked "TP" on the back along with a set of cartridge counting marks. Sized for five magazines, the magazine carrier is marked "R.I.A./4-20" on the front. The cartridge box is marked for Lot #16 on the back, and for 200 rounds of "MODEL OF 1918" 30 caliber pistol ammo on the front, along with the Remington-UMC Bridgeport address.