The FitzGerald Special, "Fitz Special", or "Fitz Colt" is a snubnosed revolver modified for concealed carry. The concept was pioneered by John Henry Fitzgerald (also known as J.H. Fitzgerald, J. Henry Fitzgerald, and "Fitz"), an employee of Colt Firearms from 1918 to 1944. Fitzgerald was a well known and respected competition pistol shooter of the 1920s and 30s and a theorist and innovator of combat pistol shooting tactics. He wrote a book entitled,Shooting in 1930, on the topics of pistol shooting techniques and tactics. There are "authentic" Fitz Specials modified by Fitzgerald himself, though the term can more generally refer to any revolver with similar modifications.
Fitz Special revolvers are made by bobbing the hammer spur, shortening the barrel to two inches, rounding the butt, and removing the front half of the trigger guard. Reshaping the hammer and the butt allows the gun to be drawn quickly with little risk of the weapon snagging on clothing. The halved trigger guard facilitates quick trigger acquisition, even for shooters with large fingers or gloves. 
Fitzgerald first came up with his concept sometime before 1926 when he modified a Colt Police Positive, whose shortest available barrel length was four inches. He later modified two Colt New Services in the same manner.
Fitzgerald built many Fitz Specials for clients. Many of these clients were law enforcement officers and soldiers.
Use in Popular Culture
The character of NYPD Police Commissioner Frank Reagan, portrayed by the actor Tom Selleck, in the television series Blue Bloods, carries a Fitz Special revolver that was given to him by his father, Henry Reagan, NYPD Police Commissioner, retired, who also carried it "on the job" and had it given to him by his late father who was also a career NYPD officer.
Book by J.H. FitzGerald
- Shooting, Hartford, CT: G.F. Book Co., 1930. [Riling 2081]
Reference is to Ray Riling, Guns and Shooting, a Bibliography, New York: Greenberg, 1951.