Colt

Colt was a pre-War weapons manufacturer in United States.

They are known for the Colt 6520 10mm pistol, Colt 6504 9mm autoloader, Colt .45 pistol and the Colt Rangemaster hunting rifle.

Mentions
Colt 6520 10mm pistol appears in Fallout and Fallout 2. Another product, the Colt Rangemaster hunting rifle, appears in Fallout, Fallout 2 and Fallout Tactics. Colt 6504 9mm autoloader was to appear in Van Buren. The Colt 45 appears in Fallout Tactics and was set to appear in the canceled Fallout Extreme.

Real world equivalent
Real-world Colt's Manufacturing Company in Wikipedia.

Colt