Review: Zenith Class 4 Chronograph

by Michael Sandler

This is a review of the Zenith Class 4 chronograph. I hope you find it useful. At the bottom of the page, there are links to MANY pictures I have taken of this watch. Please let me know what you think. For those who are interested, click here for the Zenith company Web-Site. Please note that this watch has now been renamed the Class El Primero in the 1999 Zenith literature.


El Primero Movement

The Class 4 contains the well known El Primero cal. 400 movement, made in-house by Zenith. This is a 31 jewel movement which is 30mm in diameter, and 6.5 mm thick. The movement contains 280 components, of which 225 are different. According to Zenith, the El Primero is the only chronograph movement currently in production that runs at 36,000 alternations per hour. Although this technically permits resolution down to 1/10th of a second, I have my doubts that human reaction time makes this truly useful. The ubiquitous Valjoux 7750 runs at 28,800 alternations per hour, which I believe is more than sufficient precision for a chronograph. Chronograph functions in this movement are coordinated by column wheel. The El Primero winds bi-directionally, and has a power reserve in excess of 52 hours. The image at right is from the Zenith Web-site.

The movement in this watch is not particularly well decorated. Zenith definitely seems to stress function over decoration. There are a few blued screws visible through the sapphire back, and the rotor has a pattern of radiating lines (I have been told this is called colimaconnage). The rotor engravings can be seen in the stock photo.

An additional El Primero caliber is also available (cal. 410). In addition to the functions found on the cal. 400, this movement also has day, month, and moonphase as additional functions.

Additionally, several companies buy the El Primero from Zenith. These companies include Parmigiani, Daniel Roth, Rolex (for the Daytona) and Concord (for the Impresario), and others. I have heard from a number of sources that Rolex will soon stop using the El Primero in the Daytona in favor of a newly developed in-house chronograph movement.

Dial and Hands

Zenith DialAlthough Zenith calls the dial color black, I’d say a more accurate description would be very dark gray. Under most normal lighting conditions, the dial does not appear to be totally black. The dial itself is mostly flat, although appears to curve downward slightly at its periphery. It’s surface is not totally smooth, but rather appears to be “pebbled” (for lack of a better description). The outermost portion of the dial contains a tachymeter scale. Moving inward, the next set of markers are the minute markers, followed by simple painted numbers for the hours. All hours are indicated by number with the exception of 3, 6 and 9, which are marked by small triangles. All dial markings appear to be painted on. Beneath the 12 on the dial is printed ZENITH in block letters, under which there is a script El Primero, and then AUTOMATIC in small block letters. Beneath the 6 position is printed SWISS MADE in tiny letters.

Register ImageThere are three subsidiary registers. The one at the 3:00 position is the 30 minute totalizer for the chronograph. At 6:00 is the 12 hour totalizer for the chronograph. At 9:00 is the primary second hand of the watch. Under magnification, it can be noted that the registers are textured, and not smooth like the dial. Each is made up of small concentric circles (see image).

The date is located between 4 and 5 on the dial. At first, this took some getting used to, since every other watch I’ve owned has had the date at the 3:00 position. I actually prefer this “between 4 and 5” layout, since the date window seems to “interrupt” the dial less.

The hour and minute hands, as well as the hour markers glow well in the dark, and are visible clearly even after several hours. I do not know if tritium or an alternative compound is used. Since the “T” notation is not used on the dial, perhaps it is not tritium.

Overall, I find the dial to be very legible, and well executed. Under high magnification, some of the printing appears to be slightly imperfect. This is due to the fact that the numbers were painted onto a surface that was not completely smooth (see concentric circles comment above). The printing imperfections are not noticeable to the naked eye.

Case and Crystal

Zenith Case 1 Zenith Case 2

The case of the Class 4 is stainless steel. The tops of the lugs are brushed, while the bezel and sides of the case and lugs are polished. Overall this is a pretty nice combination, leaving the watch neither too flashy nor too dull. The crown and oval chronograph pushers are polished as well. The crown contains the Zenith logo.

The case is approximately 39 mm in diameter, excluding the crown. It is about 12.5 mm thick, including the domed crystal. From lug end to lug end it is approximately 44 mm. The distance between the lugs is 19mm. Overall, if feels substantially smaller to me than the IWC Fliegerchronograph, probably due to the difference in thickness. It looks and feels less bulky than many of the other automatic chronographs I have tried.

The crystal is sapphire and domed slightly. According to Zenith, the inside of the crystal is glare-proofed, but the outside is not. Overall, glare is quite noticeable on this watch at times, although not to the level of being distracting. The case-back consists of a stainless steel ring encircling a flat sapphire window, which allows an excellent view of the El Primero movement. Engraved on the stainless steel ring is the following:






Performance and Function

Overall, performance for this watch has been nothing short of exemplary. On most days, the watch loses about 0.5 seconds. When left dial up overnight, the watch gains back approximately 0.5 seconds. Overall, since I last set this watch on February 23rd, it is +5 seconds. Remarkable!

Winding on this watch is smooth, but quite stiff. According to Zenith, this is perfectly normal. When setting the watch, pulling the crown out to the first detent allows setting of the time. Pulling the crown all the way out to the second detent allows setting the date. There is no hack feature on this watch.

The chronograph buttons operate very well, making a noticeable “click” when pressed. More pressure is needed to operate the buttons than was needed on my previous chronograph (Omega Dynamic). The movement of the chronograph second hand is extremely smooth due to the fast-beat movement. The chronograph resets to zero perfectly every time.

Bracelet / Strap

Bracelet 1
Bracelet 2

I think the bracelet on this watch is quite good, but not as good as those I’ve seen on the Omega Seamaster Pro or the Breitling Chronomat. Overall feel is solid. The clasp is hidden when closed, and can be opened by depressing two small “wings” on the underside. Each link consists of 5 pieces, the second and fourth of which are polished. The 1st, 3rd, and 5th pieces are brushed. The bracelet matches the look of the watch well.

Link removal is easy. The stainless steel pins holding the links together can be pushed out without an excessive amount of force. These pins ride inside hollow tubes, which must also be removed to separate the links. Sizing the bracelet (removal of three links) took me less than 10 minutes.

Zenith Strap 1

I really like the hidden clasp on this watch, but there is definitely one drawback. Due to the double deployant clasp, sizing the bracelet can only be made by removal or addition of a link. Small increments or decreases in size cannot be made as on a watch with a standard deployment clasp.

I also got a Zenith leather strap at the time of my purchase, although I have yet to use it. The strap is crocodile, nicely padded, with a stainless steel buckle containing the Zenith logo.


Zenith Box 1

Zenith Kit 1

The watch and all its related documentation comes inside a white cardboard outer box. The watch itself was delivered on a pillow inside a well made leather box. Overall…a very nice presentation. The watch came with a large instruction booklet (many languages), warrantee information, and a stamped warrantee card. I purchased the watch from an authorized Zenith dealer in the U.K.

Although there are no authorized Zenith dealers in the U.S. due to the ownership of the “Zenith” name by Zenith Electronics Corporation, there are 6 authorized Zenith service centers who can perform warrantee service. They are:


48 West 46th Street

New York, N.Y. 10036

Att: Mr. Joseph Kucharz

Phone (212) 575-9444

Fax (212) 768-9132


Alpha Omega

Harvard Square

57, JFK Street

Cambridge, MA 02138

Phone (617) 864-1227

Fax (617) 492-7835


Swiss Watch Service

1111 Kane Concourse Ste 500

Bay Harbor Islands, FL 33154

Phone (305) 867-8333

Fax (305) 867-8444


Swiss Connection Inc.

31271 Niguel Road, Suit E

Laguna Niguel, CA 92677

Phone (714) 488-0900

Fax (714) 488-0911


TMP Company

12549 Lake City Way NE

Seattle, WA 98125

Phone (206) 361-5198

Fax (206) 361-8619
Glezer-Kraus, Inc.

6677 N. Lincoln Avenue

Lincolnwood, Illinois 60645

Phone (847) 673-8050

Fax (847) 673-8052

There are rumors, however, that Zenith will be entering the U.S. market sometime in early 2001.


I really like this watch…A LOT. It looks great with casual clothes, and isn’t big enough to cause a problem with most shirt cuffs. The overall look is fairly conservative, and does not attract much attention. I don’t mind this at all…If I bought a watch to be noticed, I would have chosen a Rolex. As I mentioned before, timekeeping is outstanding.

My personal opinion is that this watch is a bargain. It contains perhaps the best chronograph movement (according to some) currently in production, and is available at a very reasonable price.

I would be happy to answer any questions concerning the watch or the review. simply e-mail me at (click on link)

Additional Pictures

All pictures for this review were taken with an Olympus D-600L camera. Please bear in mind that I am a complete novice when it comes to photography, let alone digital photography.

All movement pictures were taken through the sapphire back. The watch was not opened. The extreme close-ups (click below) were done by simply holding a low power loupe over the lens. All pictures are less than 160K bytes in size, so hopefully they won’t take too long to download. Resolution of each picture is in parentheses.


Picture of watch (1124 x 768)

Picture of watch (989 x 902)

Picture of watch (734 x 481)

Picture of watch (587 x 512)

Picture of watch lying on its side (910 x 668)

Low angle shot (706 x 448)

Picture of crown/pusher side of watch (640 x 248)

Picture of opposite side of watch (707 x 313)

Case Back

Picture of back of watch (1280 x 1024)

Picture of back of watch (1280 x 1024)

Picture of back of watch (1280 x 1024)

Picture of back of watch (1280 x 1024)

Picture of back of watch (642 x 626)

Picture of back of watch (1280 x 1024)


Bracelet clasp (925 x 442)

Bracelet links (537 x 288)

Movement Close-Ups

Close-up of part of movement – blued screws (331 x 357)

Close-up of part of movement – blued screws(393 x 377)

Close-up of column wheel (696 x 594)

Close-up of rotor (521 x 338)


Zenith leather strap (621 x 424)

Close-up of buckle for Zenith leather strap (381 x 309)

Outer box and papers (498 x 300)

Front of hang-tag (282 x 356)

Back of hang-tag (607 x 336)

Warranty card (498 x 300)

Copyright © 20 March 1999 Michael Sander

Updated December 4, 1999

Updated December 6, 2000

All Rights Reserved