I20 Smith & Wesson Used I Frame Blue 4" Pinned .38 CTG Regulation Police Barrel j49n Overall Length 8-1/4": Head tip

Overall Length 8-1/4": Head tip to tip 2-3/8": Head dia

357 Magnum ammunition with enhanced durability over the K Frame

A: The 15 LB spring maintains reliable ignition with most ammunition

Fitting by a qualified gunsmith may be required to ensure proper function and safety

Important: This is the new-style fluted cylinder

I20 Smith & Wesson Used I Frame Blue 4" Pinned .38 CTG Regulation Police Barrel j49n Overall Length 8-1/4": Head tipI20 Smith & Wesson Used I Frame Blue 4" Pinned . 38 CTG Regulation Police Barrel No Locking Bolt Assembly & No front Sight How to determine the model number of your Smith & Wesson Revolver. Swing out the cylinder , check behind the yoke on the frame for a MODEL NUMBER. Model numbers began in 1957 58. So if there is no model number then your revolver may be older than 1957 58. In this case we can possibly still find the part you need with the serial #