Seiko Prospex Alpinist 'Mountain Glacier' Ref. SPB117 / SBDC087
Field Watch / Sport Watch · Seiko (Seiko Watch Corporation), a leader in the premium/mid-range tier with a heritage of rugged tool watches.
Period: Modern Luxury Tool Watch Era (2020s). Stylistic indicators include the internal compass bezel, 'Cathedral' hands, and the Prospex 'X' logo on the dial.
Type
Field Watch / Sport Watch
Brand
Seiko (Seiko Watch Corporation), a leader in the premium/mid-range tier with a heritage of rugged tool watches.
Movement
Automatic, Seiko In-house Caliber 6R35; 21,600 vph (3Hz); 70-hour power reserve; 24 jewels.
Dimensions
Diameter: 39.5mm; Thickness: 13.2mm; Lug-to-lug: 46.4mm; Lug width: 20mm.
Description
The SPB117 represents the modern evolution of the legendary Seiko Alpinist. Combining the ruggedness of a field watch with the elegance of a sports watch, it features a distinct shark-tooth dial that pays homage to mid-century models while utilizing a modern 70-hour movement.
Key Features
Internal rotating compass ring, Cathedral hands, Red '20 BAR' text, shark-tooth indices, and the modern 6R35 movement upgrade.
Dial Description
Matte black dial with applied silver-toned shark-tooth/triangular indices, luminous 'Cathedral' style hands, date window at 3 o'clock with magnifying Cyclops lens, and red '20 BAR' text.
Case Material
316L Stainless Steel with Seiko's 'Super Hard Coating' (DiaShield). Featuring polished bezel and case sides with brushed upper lugs.
Crystal Type
Flat Sapphire Crystal with internal Anti-Reflective (AR) coating and an external magnifying Cyclops lens over the date.
Bezel Details
Outer: Fixed, polished stainless steel. Inner: Bi-directional rotating compass bezel operated by the secondary crown at 4 o'clock.
Crown & Pushers
Primary: Screw-down crown at 3 o'clock with 'S' branding. Secondary: Non-screw-down crown at 4 o'clock for internal compass operation.
Bracelet or Strap
Three-link 'Oyster' style stainless steel bracelet with a folding push-button deployment clasp and safety latch.
Caseback Details
Exhibition/Display screw-down caseback with sapphire or Hardlex pane, revealing the 6R35 movement and rotor markings.
Movement Type
Automatic, Seiko In-house Caliber 6R35; 21,600 vph (3Hz); 70-hour power reserve; 24 jewels.
Water Resistance
200 Meters (20 BAR/660ft). Suitable for swimming, snorkeling, and recreational diving. Screw-down crown maintenance is essential for rating integrity.
Origin & Provenance
Japan. Movement and assembly are Japanese inhouse manufacture.
Age Estimate
Modern production, circa 2020-present.
Cultural Significance
The Alpinist line has a cult-like following in the watch community, often cited as the 'perfect' everyday watch due to its versatile size and unique aesthetic history.
Condition Notes
Mint/New Old Stock (NOS). The watch is shown with factory protective plastic wrapping on the bracelet and caseback, indicating it has not been worn.
Value Estimate
Retail: $750; Secondary market: $600 - $700 depending on condition and presence of box/papers.
Care & Maintenance
Service every 5-7 years; rinse with fresh water after salt exposure; ensure crowns are fully secured before water activities; check water gaskets every 2 years.
Similar Watches
Seiko SPB121 (Green Alpinist), Hamilton Khaki Field Auto, Rolex Explorer I (visual inspiration for the black-dial field aesthetic).
Interesting Facts
The Alpinist was Seiko's first dedicated sports watch, originally designed in 1959 for Japanese 'Yama-otoko' (mountain men) who needed reliable gear for rugged terrain.