The CZ 452, also known as BRNO Model Two .22 Rifle is a series of magazine-fed bolt-action rimfire repeating rifles manufactured by the Czech firearms manufacturer Česká Zbrojovka Uherský Brod (abbreviated "CZ-UB", English: Czech Weapons Factory — Uherský Brod) and imported into the United States by CZ-USA.

During its production life, the CZ 452 was produced in several versions with various barrels, stocks and sights for a variety of rimfire cartridges such as .22 LR, .22 WMR, .17 HM2, and .17 HMR.

ZKM is an acronym for Zbrojovka-Koucký-Malorážka, the rifle's manufacturer ([Česká] Zbrojovka), designer (Josef Koucký) and Malorážka - for small calibre).

[1][2] The Model 1 or ZKM-451 was developed on the request of the occupying German authority in 1943–44, when a very few rifles were built as fully stocked Mauser 98k type trainers.

[citation needed] Because of wartime requirements for combat weapons, assembly and production was halted on all .22 training rifles, leaving a large stockpile of parts and receivers at war's end.

They sit in an American-style, straight-comb, Turkish walnut stock with checkered grip and fore-end, and is trimmed with sling studs and a hard plastic butt plate.

The barreled action sits in a varmint-style, straight-comb, walnut stock having a checkered grip with a modest palm swell and a flat-bottomed fore-end, and is trimmed with sling studs and a rubber butt pad.

The barreled action sits in a walnut stock in the European-style with checkered grip, schnabel fore-end, and arched (curved) comb sometimes referred to as a Bavarian or "hogback" stock, and is trimmed with European sling swivels and a hard plastic butt plate.

The lower drop at the heel and arched comb of the stock are designed to aid shooting with iron sights.

It is essentially the same; however, the finish of its beechwood stock has an orange hue, the top of the barrel is marked "SUPER BRNO SAA 2500," the trigger is silver in color, and it was provided with a 5-round magazine.

These are reported to have originally been produced as training rifles for Egypt, who refused, at which point CZ made them available to the public.

It has a shortened beechwood stock with a straight, slightly dropped comb, and a blued metal finish.

It is essentially a CZ American action and barrel in a synthetic stock with a raised comb and cheek piece.

The Style is identical to the Silhouette except that it features a matte nickel electroplate finish on all metal surfaces except for the bolt and trigger assemblies.

Released in 2017, the Grand Finale is a limited run of 1,000 rifles to commemorate the CZ 452 line.

It follows the pattern of the CZ 452 American, but features an oil-finished walnut stock with ebony fore-end tip and grip cap, is hand engraved with a high polish blued finish, has a gold plated trigger, and features a custom metal magazine floor plate.