There were twenty five Coast Guard guns with fixed service sights. This is mine. It belong to Ed Pomeroy, who designed the Coast Guard guns. I believe, until some one proves me wrong, that 0366 is the prototype for the Coast Guard guns. It was given to Pomeroy on January 21, 1935. The 25 Coast Guard guns shipped February 12, 1935. Here is the write up from the auction catalog from March 2024.
0366 22 LR, 6" pinned round barrel with a bright excellent bore. Already rare and desirable with its special purpose "0" prefix serial number, this revolver is further enhanced by the fact that it is equipped with fixed service-style sights and was shipped, according to our correspondence with Roy Jinks, on January 21, 1935 to Edward S. Pomeroy, Smith & Wesson plant superintendent and designer. Mr. Pomeroy was the designer of Smith & Wesson handcuffs, moon clips, their 32 Automatic pistol and the Model 1940 Light Rifle, among others. Only a handful of K-frame revolvers in 22 LR with fixed service sights were manufactured for various special contracts. This example would have been made around the time of the 25-gun U.S. Coast Guard contract which was for revolvers in this exact configuration with fixed sights. The arm is also in superb condition retaining about 99% original blue showing just a hint of subtle operational wear and a couple tiny handling marks. The serrated service trigger and hammer show lovely vibrant case-hardened colors throughout and all markings remain crisp and clear. The checkered walnut grips with silver S&W medallions remain in excellent condition showing just a tiny drying crack above the left medallion. The right panel is stamp-numbered "651720" and their fit is perfect; that serial number puts it not long after the USCG contract guns (650929-650953). The revolver includes an original un-numbered factory red box with gold lettering and image of revolver that remains in fine condition showing some overall edge wear and light scuffing.