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 640, is a variation of the Model 40 Centennial which integrates the time-tested features of the original with modern advancements. It is a small-frame, concealed-hammer revolver that packs a full-sized punch. This model has a stainless steel frame barrel and cylinder, blade front and fixed rear sights, and black synthetic grip.
| Frame Size | J-Frame |
| Frame Description | Stainless Steel Frame |
| Type | Revolver |
| Caliber | 38 Special +P |
| Barrel Length Range | 2" to 2.99" |
| Grips | Black Finger Grooved |
| Cylinder Finish | Satin |
| FireArm | yes |
| Capacity | 5 |
| Hammer Style | Concealed |
| Sights | Blade Front/Fixed Rear |
| Barrel Length | 2.12" |
| OAL | 6.56" |
| Weight | 22.10 oz |
| Weight Range | 16 oz to 31.99 oz |
| Action | DAO |
| Barrel Finish | Satin Stainless |
