Independent watchmaker Kari Voutilainen made the glacial blue guilloché main plate at the heart of Armin Strom's latest Gravity Equal Force.
Armin Strom today introduces the Gravity Equal Force Ultimate Sapphire Blue, a cooler, glacial-toned edition of its System 78 watch, produced in a limited annual series of 25 pieces.
Housed in a 41mm steel case, the open dial sits asymmetrically on the left, its transparent sapphire revealing the silvery movement beneath. The micro-rotor, equal-force barrel and finger bridges are hand-finished in rhodium to match the gear train, and a blue nubuck strap ties the palette together.
Calibre ASB19 is, the brand says, the first automatic movement with a stop-work declutch and a Geneva cross inside the barrel. The system holds the force on the balance constant through the full 72-hour power reserve. Every part is bevelled, polished and black-finished by hand in Armin Strom's manufacture in Biel, with perlage, Geneva stripes and circular graining, and the watch is assembled twice.
The Basics
Brand: Armin Strom
Model: Gravity Equal Force Ultimate Sapphire Blue
Reference: ST24-GEF.BLU
Diameter: 41mm
Thickness: 12.65mm
Case material: Stainless steel; sapphire crystal and case back
Dial: Grey-toned, off-centre sapphire crystal with subdial; glacial blue guilloché main plate by Kari Voutilainen
Water resistance: 3 ATM
Strap: Blue nubuck leather with ice blue stitching and keepers; stainless steel folding clasp
Limited edition: 25 pieces per year
The Movement
Calibre: ASB19, automatic with micro-rotor
Functions: Hours, minutes, seconds, power reserve indicator; patented equal force barrel
Winding: Automatic, micro-rotor
Power reserve: 72 hours
Frequency: 3.5Hz (25,200 vph)
Jewels: 28
Images courtesy of Armin Strom.