Smith & Wesson J Frame Model 640-3 & Up Hammer & Trigger .357 Magnum MIM New Style Used mp-shield-40-10 320" width and smooth face

320" width and smooth face for consistent

This is a genuine Smith & Wesson factory replacement cylinder assembly in classic blue steel finish

Factory-original part manufactured to exact specifications

This is a critical fire control component requiring proper fitting and function testing for safe operation

Smith & Wesson J Frame Model 640-3 & Up Hammer & Trigger .357 Magnum MIM New Style Used mp-shield-40-10 320" width and smooth faceSmith & Wesson J Frame Model 640 3 & Up Hammer & Trigger . 357 Magnum MIM New Style Used (Part# J6403) This listing is for one used Smith & Wesson J Frame Model 640 Centennial hammer and trigger assembly for dash 3 and later variants. These are MIM (Metal Injection Molded) parts in the new style configuration, introduced with the 640 3. This is an OEM factory assembly in used condition, removed from a functioning firearm. Compatibility note: This