Smith & Wesson J-Frame revolver is designed to fire a full power round and is as simple and easy to use as it is reliable. The Model 637 is a variation of the Model 37 Chiefs Special Airweight which integrates the time-tested features of the original with modern advancements. It is ultra-light and is a favorite back-up and concealed carry firearm. This model has an aluminum alloy frame, stainless steel barrel and cylinder, integral front and fixed rear sights, and an external hammer. It also has black synthetic grip.