Verified Evaluation
Seiko Caliber 6R55 Automatic (72-Hour Power Reserve)
Technical Dossier // Japan
Evaluator: @sierra.66.actual
Seiko Prospex 62MAS Diver SPB453
5.0 / 5.0
| 300m / 30 ATM WR MSRP at Review: $1,300
// SBWC Field Verdict
Strengths
- + Upgraded 300m water resistance over previous 200m generation
- + 3-day (72-hour) power reserve from upgraded Caliber 6R55
- + DiaShield super-hard coating resists field and workshop abrasion
Operational Limitations
- - Bezel insert remains aluminum rather than ceramic
- - Stock clasp lacks on-the-fly micro-adjustment
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Complete Specifications
Factory & Field Architecture
Movement Seiko Caliber 6R55 Automatic (21,600 vph, 24 Jewels, Hacking)
Power Reserve 72 Hours (3 Days Extended Power Reserve)
Case Dimensions 40.0mm diameter, 13.0mm thickness, 46.4mm lug-to-lug
Lug Width 20mm
Water Resistance 300M / 30 ATM ISO Certified Diver
Luminescence Seiko LumiBrite on Hands, Indices, and Bezel Pip
Crystal Curved Sapphire Crystal with Anti-Reflective Inner Coating
Case Coating DiaShield Super-Hard Stainless Steel Surface Treatment
Origin Engineered & Manufactured by Seiko Watch Corp, Japan
Field Evaluator @sierra.66.actual (Post-Service Industrial Welding Trades)
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