Chicago-area buyers tend to wait for a pistol to prove itself before they commit, but a new CZ striker gun gets attention quickly. The DUTY 4.0 is CZ's next-generation 9x19mm, and its big idea is the serialized modular chassis: the serial number sits on the internal unit, and the fiberglass-reinforced polymer grip frame around it is the swappable part. CZ offers it as the C compact (15+1 rounds, 5.3 inches tall) and the F full-size (17+1, 5.6 inches tall), and both sizes come as MS models with a manual thumb safety.

From Naperville and Joliet in the collar counties, out to DeKalb, Ottawa, Rockford, Peoria and Galesburg, Illinois owners use a pistol like this for home defense, for the range and for concealed carry where they are licensed. The trigger is CZ's refined SFDA with a 4 mm reset, the barrel is 4 inches, and the slide takes a red dot by direct mount with fixed sights alongside.

Three things define the DUTY 4.0. First, a registered modular chassis: the registered part is inside, the frame module around it is modular. Second, the trigger, a striker SFDA rated at 25 ± 4 N (5.6 ± 0.9 lbs), 4 mm (0.16 in) reset, 9 ± 1 mm (0.4 ± 0.04 in) travel, which is short and repeatable for a service pistol. Third, a direct-mount optics-ready slide, shown by CZ with Holosun, Aimpoint and Shield dots fitted, so a dot sight sits low without a stack of plates.

This is the longer grip of the two DUTY frames. It holds 17+1 rounds, 19+1 with the extended plate, stands 143 mm (5.6 in) and weighs 780 g (27.7 oz) unloaded. Same slide, same 4-inch barrel as the carry-size, so the sight radius is identical; you buy the F for the grip and the extra rounds.

The standard model skips the manual thumb safety and keeps the three passive ones: firing pin block, trigger safety and trigger-bar safety. Same chassis, same trigger and slide as the MS; only the lever is missing.

The CZ DUTY 4.0 F suits anyone who wants a modern optics-ready 9mm with CZ's grip and a trigger that is better than the class average: home defense, duty use, competition and long range sessions where the extra grip and two more rounds matter.

Illinois buyers need a valid FOID card, and the dealer holds the pistol at least 72 hours before pickup. We ship the DUTY 4.0 to the Illinois dealer you name at checkout, and that dealer handles the hold and the background check. Ammunition and gear ship to your door once your FOID is on file. Before you pay, stock and price are verified live.

Questions buyers ask: How long does my Illinois dealer hold the DUTY 4.0 before I can pick it up? At least 72 hours, and you need a valid FOID card. Your dealer runs the check and sets the pickup time. Is the trigger heavy? CZ rates it at 5.6 pounds plus or minus 0.9, with 9 mm of travel and a 4 mm reset. It is a service trigger, not a competition one. How many rounds does the CZ DUTY 4.0 F hold? 17+1 with the standard magazine and 19+1 with the extended floor plate.