[1] Officially designated .450 Boxer Mk I, and also known variously as the .450 Revolver, .450 Colt, .450 Short, .450 Corto, and .450 Mark III, and in America as the .45 Webley,[2] it was the British Army's first centrefire revolver round.

[2] Despite the different designations, the .450 may be fired in any weapon chambered for .455 Webley,[2][3] .455 Colt, or .476 Enfield.

[4] While not considered a suitable military round,[2] the .450 Mark III cartridges did serve in reserve for the British armed forces as late as the First World War.

[2] The .450 Adams also proved popular among civilian users of Webley RIC and British Bulldog revolvers, being loaded in Europe, and persisting in the United States until around 1940.

Both Colt and Smith & Wesson offered revolvers in .450 Adams.