This is a Smith & Wesson Double Action Only known as the 642 chambered in 38 Special, model 178042.
Smith & Wesson J-Frame revolvers have had your back since 1950. These small revolvers were designed to fire a full power round and are as simple and easy to use as they are reliable. Available in various calibers and with three diverse hammer designs" it is no surprise that the Smith & Wesson J-Frame has become the most popular" small-frame" defense revolver on the market. The Model 642 Pro Series is a variation on the Model 42 Centennial Airweight that integrates the time-tested features of the original with modern advancements and competition specifications and features.
Features:
Stainless finish
Lightweight alloy frame
Stainless steel barrel
Cylinder cut for moon clips
Snag-free enclosed hammer
No internal lock