The Smith & Wesson SW1911PD is a pistol.
Retired NIS/NCIS Special Agent Mike Franks carries this weapon as his personal sidearm and he is seen holding as well as using this gun during the Season 5 finale episodes, Judgment Day Part 1 (episode) and Judgment Day Part 2 (episode).
In the Season 6 episode, Deliverance (episode), Franks once again uses a Smith & Wesson SW1911PD as his sidearm.
In the Season 7 episode, Rule Fifty-One (episode), Franks's Smith & Wesson SW1911PD is seen again.
It appears in the Season 8 episode, Pyramid (episode) with serial killer, Lieutenant Jonas Cobb stealing it after he kills Mike Franks.
The weapon makes its final physical appearance in the Season 8 finale episode, Swan Song (episode) with Cobb holding it as a weapon.
In a dream sequence seen in the Season 10 finale episode, Damned If You Do (episode), Franks can be seen using the Smith & Wesson SW1911PD.