Luca Soprana — Mécanique d'émotion
by Luca Soprana · Remontoir d'Égalité
Derek Pratt by Luca Soprana — Calibre DP07 caseback movement
Collection  /  Derek Pratt

Derek
Pratt.

A constant-force wristwatch Derek himself never had time to finish — built around his signature Reuleaux-triangle remontoir, rebuilt from the ground up at Atelier SMA with the blessing of his family.
Calibre DP07 · 41.6mm GPHG finalist · 2025

Finishing a legacy.

« Not about noise or marketing. About making the key mechanical idea visible, hiding everything that is not essential, and finishing every component by hand — slowly, honestly. »

Years after first seeing Pratt's prototype, Luca returned to the project with the blessing of Derek's family and rebuilt it from the ground up — redesigning the calibre to honour Pratt's aesthetic and technical standards, bringing his pocket-watch chronometry into a slim, contemporary wristwatch made in only a handful of pieces.

Behind this watch is the philosophy of Luca's atelier: a small, discreet workshop that has long been the invisible backbone behind high complications for others — now signing its own name next to Pratt's. A quiet, deeply considered piece for collectors who care more about substance and lineage than hype.

Key elements.

Three pillars
Calibre DP07 — twin barrels, balance, remontoir
№ 01

DP07 Movement

Hand-wound, developed in the atelier to finally bring Pratt's Reuleaux triangle remontoir from pocket to wrist. Twin suspended barrels feed a one-second constant-force remontoir coaxial with the escape wheel, driving deadbeat seconds at seven o'clock.

Steel case — silvered Roman dial
№ 02

Steel or platinum case

316L stainless or platinum. Approximately 41.6 mm in diameter and 12.6 mm thick. Polished bezel and lugs contrast vertically brushed case flanks. Front and back sapphire — the movement becomes a mechanical landscape on the wrist.

Salmon dial · Arabic numerals · tan strap
№ 03

A sophisticated dial

The main collection's dial is finely textured, with an off-centre small seconds at seven o'clock and a classical Roman-numeral chapter — the configuration selected as a finalist for the 2025 GPHG. Slim, heat-blued hands and a discreet Derek Pratt signature complete a dial that feels deliberately understated. Salmon and Arabic-numeral variants are also offered.

DP07 Remontoir macro
Reuleaux-triangle remontoir · by Pratt · completed by Soprana
Derek Pratt by Luca Soprana — silvered Roman dial · official render
Silvered Roman dial · Ref. DP07-RN · official atelier render

The remontoir —
in motion.

Calibre DP07 · running

The deadbeat seconds advancing under the Reuleaux-triangle remontoir — exactly one jump, every second, driven by the constant-force mechanism. Sound muted intentionally; the mechanism speaks for itself.

Technical dossier.

Derek Pratt was an extraordinary watchmaker — a contemporary of George Daniels, and like Daniels, obsessed with mechanical precision. Unlike him, he never produced a wristwatch under his own name before passing in 2009. That is, until now.

Calibre DP07 · Ref. DPLS · A handful of pieces
Calibre
DP07 · hand-wound
Complication
Remontoir d'égalité · 1 second
Cam geometry
Reuleaux triangle · coaxial with escape wheel
Seconds
Deadbeat · at 7 o'clock
Barrels
Twin · suspended · motor-barrel config
Balance
Large · free-sprung
Power reserve
≈ a day and a half · 36 hours
Diameter
41.6 mm
Thickness
12.6 mm
Case
316L stainless steel or platinum
Dial (main)
Grey · finely textured · heat-blued hands
Dial (variant 1)
Silvered · tan strap
Dial (variant 2)
Salmon · Arabic numerals
Chapter ring
Roman numerals · small seconds at 7
Finishes
Sharp anglage · frosted & brushed surfaces
Recognition
GPHG 2025 finalist
Production
A handful of pieces · by hand

2026 prices.

A constant-force wristwatch built from the ground up to honour Derek Pratt's legacy. Each piece is hand-finished in the atelier — production is intentionally tiny, and orders are subject to a waiting list.

Calibre DP07 · Ref. DPLS · A handful of pieces per year
From
CHF 135,000 + taxes · stainless steel
Platinum
On enquiry
Dial options
Grey · silvered Roman · salmon Arabic
Production
A handful of pieces · GPHG 2025 finalist
Delivery
By agreement · after a conversation

The waiting list.

« Each Derek Pratt by Luca Soprana is built slowly, by hand, with the blessing of Derek's family. »

Production is deliberately limited. To be considered, please write to us with a short note about yourself and your interest in the piece.

Join the waiting list →