If you haven’t heard that term before, that makes two of us, but trust me; I’ll explain. The CHPTR_Δ.5 (pronounced “Chapter Delta point five” in case you were stumbling) is the lovechild of BA111OD and Label Noir, designed by Thomas Baillod. It is a triangularly different, semi-open-worked creation with a dark vibe.

This comes in a month when more modern pieces seem to emerge, even if retro is still the flavor of the last decade. Whether or not this watch reflects the times, the avant-garde pops of green within a dark dial come at a tempting price. Accessibility is the way forward for this futurist watchmaking branch, and BA111OD and Label Noir get it.

Introducing The Stealthy Allure Of The CHPTR_Δ.5 By BA111OD x Label Noir

The BA111OD CHPTR_Δ.5 Label Noir Limited Edition

Label Noir has a story of curated watches in collaboration with some of the more niche brands in Switzerland. This time, we get 111 pieces of dark stealthiness with a fresh hint of green in the details. At €3,650, this watch also surprised me with its relative affordability. This is a good price for the innovation and tech involved in this piece. It was just slightly over budget for my appropriately titled “Futurism For Less Than €3K” story last week. And if you’re still wondering what the heck “hypocycloidal” means, I will don my lab coat in a minute to explain.

Introducing The Stealthy Allure Of The CHPTR_Δ.5 By BA111OD x Label Noir

First impressions

The vibe of the enigmatically named CHPTR_Δ.5 riffs off brands like De Bethune, Urwerk, and MB&F. They are all brands that operate in an entirely different sphere of wrist investment, and that is a big compliment. BA111OD is a young brand based in Neuchâtel. It was founded only four years ago but is already making its mark. With the CHPTR_Δ series, brand founder Thomas Baillod presents BA111OD’s first manufacture complication and says: “Since day one, BA111OD has been about a different way of looking at watchmaking. Today, we offer a new reading of time as well.”

Introducing The Stealthy Allure Of The CHPTR_Δ.5 By BA111OD x Label Noir

This watch shows a curvy triangular bridge structure with three cardinal points of 4, 8, and 12 marked alongside nine other hour markers. This sits atop an indented and logoed black chapter ring where the minutes are rendered in crisp white, overlaid by a semi-skeletonized minute hand with green lume. But where is the hour indicator? Have a look at the centrally rotating arrow shape, which has a lollipop tip that moves independently and, yes, hypocycloidally. Let me explain.

Introducing The Stealthy Allure Of The CHPTR_Δ.5 By BA111OD x Label Noir

Hypocycloidal charm

Do you see the lumed lollipop-shaped end? Instead of using a centrally rotating hand, the movement was designed to “roll” a satellite hour wheel around a fixed central hour wheel. Still with me? When this is in place, the trajectory at any point on this satellite wheel is a cycloid. There are several types of cycloids, and in this new chapter for BA111OD, the chosen cycloid is a deltoid (the shape, not the muscle group).

As a result, the trajectory of the tip of the hour hand is a triangle. BA111OD’s watchmaker Olivier Mory says, “There is hardly anything but the transcendent beauty of mathematics to obtain a triangle using only things that rotate in circles! It is a discreet tribute to the several centuries-old use of the cycloid in watchmaking. Galileo, Newton, Huygens, Euler, Cantor, or Roberval, to name a handful…” So far, it’s scientifically charming in a big way. The designers at BA111OD have even managed the Easter egg of a discrete date window at 2 o’clock, tucked away in the shadows.

Does size matter? — A self-inflicted debate

Is 44mm too big, or is 38mm too small? Does it matter? Yesterday, I wore a 37mm Grand Seiko, and today, I’m wearing a 44mm Aera D-1, even while writing. That’s because ergonomics are key, and size only matters if you let it. The charms of the CHPTR_Δ.5 come set within a 44mm frame, and to my mind, it is worth it for the avant-garde dial view. It is set in a brushed and polished PVD black steel case. Neither BA111OD nor Label Noir gives us the lug-to-lug, but I’d say it is a 47–49mm span from the images. This works well with what seems to be a good downward curve, and the big crown is tucked in neatly at 4 o’clock.

Introducing The Stealthy Allure Of The CHPTR_Δ.5 By BA111OD x Label Noir

Besides size being relative, this is not about being an everyday beater. It’s a sports watch but never a GADA piece, God forbid. It’s that special wild-card watch for one’s collection, yet the price is rather good, with the complexities based on a Soprod M100 caliber. With only 111 pieces being made, CHF 2,950 / €3,650 / US$3,750 is very reasonable. Check out more details on the BA111OD website, where pre-orders are open.

My dear Fratelli, does the stealthy allure of the CHPTR_Δ.5 inspire your taste for futuristic watch design? Let me know in the comments. I, for one, found this rather tempting.

Watch specifications

CHPTR_Δ.5 Label Noir Limited Edition
Black satin-finished steel with multiple levels and laser engraving, faceted triangle with black PVD treatment, green accents
Case Material
316L stainless steel with black PVD coating, polished and brushed finishes
Case Dimensions
Domed sapphire with AR coating
Case Back
316L stainless steel with black PVD coating and sapphire crystal
Soprod M100 with BA111OD-manufactured module 09310: automatic and manual winding, 28,800vph frequency, 42-hour power reserve, hypocycloidal time display
Water Resistance
5 ATM (50 meters)
Black textile with green stitching, deployant clasp, and easy-clip system
Time (hours, minutes) and date
CHF 2,950 / €3,650 / US$3,750
Two years