Constitutional Arms Multi-Ammunition Pistol

Constitution Arms Mulit-Ammunition Pistol is revolver designed by Constitution Arms to take advantage of advances in the field of ordnance technology, this revolver is designed to offer the user a choice between lethal and non-lethal response to a situation. The standard model is equipped with a rapid selector switch (to select between rounds before firing) and a readout display under the rear sight, which informs the user of the round selected. Smartchipped models give the user direct control over selection, and round information is provided directly to the user (requires Time Square Marquee). Being a revolver, it uses cased ammo; see the Ammunition section for further details.

Source

 * Protect & Serve, pg.32
 * Blackhand's Street Weapons, pg.16