Manufactured by Smith & Wesson for Mercox circa 1967. According to Supica and Nahas in the STANDARD CATALOG OF SMITH & WESSON, this is one of 25 dart projectile guns manufactured by Smith & Wesson with 17 to 18 reportedly shipped. With very few made, the authors concluded that it is possible that this gun was experimental only. This handgun type device is based on a K-22 frame and was designed to deliver hypodermic dart syringes or other types of materials such as teargas, dye, or explosive or crowd control projectiles. It has a standard Model 17 K-22 square butt frame, walnut grips featuring S&W medallions, hammer and trigger. A 12 1/2 inch barrel with an adapter is attached to the frame and uses a special .22 caliber cartridge as a propellant. The right side of the frame is stamped with the S&W logo and the S&W Springfield address. The checkered hammer and serrated trigger have a casehardened finish with the remaining metal surfaces blue. The nicely figured extended grips are checkered and feature S&W medallions. Included is the S&W blue box and 11 promotional type pamphlets.