The Ferdinand Berthoud Chronomètre FB 1RES.4 is a 44 mm, hand-wound skeleton watch built around a fusee-and-chain transmission and a one-second remontoire. Its openworked architecture puts those mechanisms on display, while the deadbeat seconds hand makes the remontoire’s once-per-second action visible. This is a collector-oriented interpretation of high horology, not a conventional daily-wear recommendation.
What the FB 1RES.4 is—and what makes it unusual
The FB 1RES.4 pairs an octagonal, ceramic-coated titanium case with an anthracite sand-blasted, openworked nickel-silver dial. Its hand-wound FB-RES.FC calibre combines two approaches to managing the energy delivered to the escapement: a fusee-and-chain transmission and a one-second remontoire. The result is both a technical proposition and the watch’s visual subject.
Ferdinand Berthoud says the three-bridge arrangement takes inspiration from a skeletonised table clock made by the watchmaker around 1775, which also featured a remontoire d’égalité. That historical connection is the manufacture’s account of the design inspiration.
How the fusee, remontoire and deadbeat seconds work together
Fusee and chain
As a mainspring unwinds, the force it supplies changes. The fusee-and-chain transmission is intended to address that changing force before it reaches the rest of the mechanism. In the FB-RES.FC, it forms the first part of the calibre’s energy-management system.
The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →#1 Best Overall
- 【Stunning Skeleton See-Through Dial】The men's watch features fully transparent skeleton dial showcases the intricate automatic mechanical movement, letting you witness the precise operation of every gear in real time. Paired with a high-contrast black dial and classic Roman numeral hour markers, it delivers a unique, luxurious and sophisticated look that highlights your personal taste.
- 【Self-Winding Automatic Mechanical Movement, No Battery Required】The automatic watch is equipped with high-precision self-winding mechanical core, powered solely by the natural movement of your wrist during daily wear. No need for battery replacement, low maintenance, and delivers stable, accurate timekeeping for long term reliable daily use.
- 【Premium Silver Stainless Steel Construction for Durable Daily Wear】The analog watch is crafted with high-quality solid stainless steel for both the 42mm case and bracelet, with a polished silver finish. It is anti-scratch, anti-corrosion and anti-abrasion, built to withstand daily wear and tear, ensuring long-lasting durability and a premium hand feel.
- 【High-Readability Black Dial for All Day Use】The wrist watch black dial features precise clear markings, luminous hands and exquisite decorative details. The high-contrast design ensures effortless time reading at a glance, while the luminous function guarantees clear time display even in low-light or dark environments, enhancing the watch's overall luxury texture.
- 【Elegant Gift Box Included, Ideal Gift for Men】The mechanical watch is a perfect present for birthdays, anniversaries, graduations, Father's Day, Christmas and other important holidays, suitable for every gentleman.
One-second remontoire
A small spring positioned between the power train and the escapement acts as a buffer. The manufacturer says it is charged and discharged once per second, releasing a small, regular amount of energy to the escapement. This is the remontoire’s stated role; it should not be read as a guarantee of a particular real-world accuracy result.
Why the seconds hand jumps
An intermediate wheel connects the remontoire to the central seconds hand. As the remontoire releases its energy each second, the hand advances in one-second steps—a display known as deadbeat seconds. Here, the complication is not merely a dial-side flourish: it makes the calibre’s one-second rhythm legible.
Rank #2
- 【Hollow Skeleton Design】 Luxury skeleton hollow-out design allows you to have a beautiful vintage watch with the appearance of a mechanical watch, but you don't need to wind it up every day like a mechanical watch.
- 【Novel Style】 The unique long barrel shape surface is distinguished from the square round watches on the market. The front and back sides have gorgeous gear carving design. There are 4 different color cases to choose from, and the steel belt and belt are matched at the same time. A total of 9 colors are optional.
- 【Comfortable to Wear】 Durable leather strap is easy to adjust the length; The buckle of the stainless steel watch strap is a hidden button buckle, which is more convenient to wear and remove. The luminous pointer lets you see the time of the night.
- 【Good Quality】 The high-strength mineral glass on the case provides scratch protection. High quality case, not easy to fade. Waterproof to 30 meters (only for domestic waterproof, i.e. splash-proof and sweat-proof, not for bathing and diving)
- 【Exquisite Gift】 This fashionable hollowed-out skeleton watch is suitable for any casual or formal occasion. Its elegant appearance is easy to match with any men's clothing, making your wrist the focus. Unique design, exquisite craftsmanship, luxurious appearance and exquisite packaging are perfect gifts for holidays, Thanksgiving, Christmas, graduation, Father's Day and birthday.
What you can see through the openworked dial
Three bridges converge toward the centre of the dial, framing visible components rather than hiding the movement behind a conventional dial. Openings in the anthracite dial plate and sapphire windows provide further views into the mechanism. The front has a domed sapphire crystal with anti-reflective treatment on both sides, plus sapphire portholes at 2 and 11 o’clock; a sapphire case-back offers another view.
The hands are deliberately varied: gilded, skeletonised dagger-shaped hour and minute hands; a blue CVD-treated brass central seconds hand; and an 18-carat gold, arrow-shaped power-reserve hand with blue CVD treatment. The manufacture says each wheel, bridge and screw receives hand decoration, and reports more than two linear metres of hand-filed and polished angles across the wheels, bridges and power-reserve display.
Do these 3 things before closing this tab:
1Fix the driver behind crashes, sound loss and screen glitches2Repair Windows errors before they cause bigger problems3Scan for outdated or missing drivers - takes under a minuteRank #3
- STEAMPUNK SKELETON DESIGN – Exposed gears and intricate mechanical movement visible through the dial create a striking vintage-industrial aesthetic. Rose-gold and silver two-tone case with Roman numerals adds timeless elegance. A conversation-starting timepiece that consistently draws compliments
- HAND-WIND MECHANICAL MOVEMENT – Powered by manual winding, no battery needed. Simply turn the crown 20-25 times for a full wind. Reliable analog movement keeps accurate time for daily wear. Embrace the traditional craftsmanship of mechanical watchmaking
- CLASSIC ROMAN NUMERAL DIAL – Bold Roman numerals and luminous hands ensure easy reading in any light. Exhibition case back reveals the intricate inner workings. 40mm case diameter with 12mm thickness offers substantial presence without being overly bulky
- COMFORTABLE BROWN LEATHER STRAP – Soft genuine leather band fits comfortably against the wrist. Adjustable buckle closure accommodates various wrist sizes. Versatile brown color pairs well with both casual and business attire
- VERSATILE ACCESSORY FOR ANY OCCASION – Transitions effortlessly from office to weekend. Suitable for work, travel, festivals, or everyday wear. A unique fashion statement that pairs well with suits or casual outfits. 3ATM splash-resistant for daily hand-washing and light rain
FB 1RES.4 specifications
| Feature | Manufacturer specification |
|---|---|
| Case | Octagonal titanium with ceramic coating; 44 mm diameter; 14.26 mm thick |
| Water resistance | 30 m |
| Crystal | Domed sapphire, anti-reflective on both sides; sapphire portholes at 2 and 11 o’clock; sapphire case-back |
| Movement | Hand-wound FB-RES.FC; fusee-and-chain transmission; one-second remontoire |
| Movement dimensions | 37.30 mm diameter; 9.37 mm thick; 16½ lignes |
| Movement details | 58 jewels; 1,200 components; 18,000 vph (2.5 Hz); stated 50-hour power reserve; chain length listed as 285, with no unit stated |
| Certification | COSC chronometer-certified |
| Functions | Hours, minutes, deadbeat seconds, power reserve; time-setting with stop-seconds device on the balance |
| Dial and hands | Anthracite sand-blasted openworked nickel-silver plate; gilded skeletonised hour and minute hands; blue CVD-treated brass central seconds hand; 18-carat gold arrow-shaped power-reserve hand with blue CVD treatment |
| Strap and buckle | Alligator leather; length-adjustable double-blade folding clasp or pin buckle |
| Production | Manufacturer states 38 movements will be produced for the FB RES |
These figures are the manufacturer’s product specifications, not independent measurements. COSC certification is stated for the movement; the material available does not establish an independent accuracy test of this specific watch.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Fit, wearability and the customization question
The 44 mm diameter and 14.26 mm thickness make this a substantial watch on paper. Its titanium case keeps the case material distinct from a heavier precious-metal construction, but the supplied specifications do not give a weight or establish how it wears on different wrists. The 30 m water-resistance rating is modest: treat it as a watch for careful wear rather than swimming or water sports.
Rank #4
- 【Full Openwork Skeleton Design – For True Watch Enthusiasts】Wearable mechanical art with fully exposed gears, watch intricate movements spin in real time. Blue accent adds modern sleekness, perfect for business meetings or casual outings—stands out without being flashy.
- 【Pre-Calibrated Automatic Movement – Accurate & Battery-Free】Factory pre-calibrated for ±20 seconds/day accuracy (mechanical watch standard). Self-winding via wrist motion—no batteries. First use: manually wind 30-40 times for stable timekeeping, ideal for daily/business/travel.
- 【304 Stainless Steel Build – Scratch & Rust Resistant】 Durable 304 stainless steel case/band, scratch-proof, rust-proof, lightweight for all-day comfort. Transitions seamlessly from office to outdoor activities (hiking, running).
- 【 30M Daily Waterproof – Handle Life’s Minor Splashes】 3ATM waterproof for hand washing, rain splashes, accidental spills. NOT for swimming/showering/diving—protects delicate mechanical movement.
- 【Perfect Gift & Worry-Free Service】Elegant gift box for birthdays/anniversaries/Father’s Day. 1-year warranty + 30-day hassle-free return. 24/7 customer support for any issues.
There is a specification conflict worth noticing if you encounter retailer listings: the manufacturer gives 30 m, while Pisa 1940 lists 50 m/5 atm. The manufacturer’s figure is the safer reference for this article.
Customization is part of the wider FB RES proposition, not a description of every setting on this exact example. In its 2 April 2024 announcement, the manufacture said the configurator could simulate more than 200 variations, including options for case shape and material, bezel-ring colour, and dial colour and finish. The 1RES.4 configuration described here is specifically ceramic-coated titanium with an anthracite sand-blasted dial.
Recommended Free Tools
Best Value
- Carbon Fiber Case: Multi-layer skeleton design with CNC cutting technology. Innovative thick case is frame of carbon fiber which ensure ideal shock resistance. The tonneau dial shape combines classic and modern design.
- Stylish Automatic Watch: Interesting skeleton design and transparent see-through back cover with the mechanical movement clearly visible, a strengthened sense of metal and sharp lines. Cool appearance brings the wearer unique fashion sense.
- Transparent HD Material: Equipped with a colorless anti-reflective coating synthetic sapphire mirror surface, wear resistant, highly translucent. This dial window is hard and scratch resistant. Luminous markers, clearly visible in the dark.
- High quality silicone strap is sweat, moisture and corrosion resistant and comfortable to wear without any allergic reaction. Wear this watch on the go, from business, leisure to indoor and outdoor activities or for daily use.
- 30M Waterproof: Water resistant to rain, hand washing, splash, brief immersion in water, offering reliable performance for everyday use. Avoid pressing any buttons while in water to maintain optimal functionality.
Availability and price
The manufacturer states that 38 movements will be produced for the FB RES; that announced production quantity does not indicate how many watches remain available. The manufacturer invites acquisition inquiries but does not publish a price on the cited product page. Pisa 1940 lists the reference as “Price on request.” For current availability, price and terms, contact the manufacture or a luxury-watch retailer directly and confirm the retailer’s authorized status.
Who this watch is for
The FB 1RES.4 makes the most sense for a collector drawn to the mechanics as much as the object: someone who values a visible constant-force architecture, a jumping central seconds display and extensive hand finishing. It is less straightforward as a single do-everything watch, given its large stated dimensions, modest water resistance and unusually exposed, technical dial. Without sourced facts for comparable watches, it is better understood on its own terms than ranked against other high-horology pieces.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
