He includes CC under duty.
Here are the basic specifications to examine for a duty 1911:
•Full sized Government Model 1911 format with 5" barrel length and steel frame for increased reliability and durability.
•Chambered in .45 ACP, as that is the caliber in which the gun was designed and functions best. The greatest number of magazine options are available in .45 ACP.
•Standard Browning barrel without integral feed ramp. Ramped barrels typically have very steep feed ramps that don't feed well. Wide mouthed hollowpoints can also catch at the bottom of the integral ramp, creating further feeding issues.
•Standard milspec short recoil spring guide rod and plug.
•Recoil spring rating of 17-18.5 lbs to improve durability with full power duty loads.
•Availability of ambidextrous safety for left handed users.
•Type of firing pin safety system, if any. See below for further.
•Light rail or standard dust cover.
•Type of finish.