Longines Master Collection Moonphase vs Seiko Prospex "Turtle"
Longines's dress watch meets Seiko's diver
Quick Verdict
The Seiko Prospex "Turtle" (~$500) delivers In-House Automatic Manufacture technology at $2,500 less than the Longines Master Collection Moonphase (~$3,000). The Master Collection Moonphase justifies its premium with Swiss Made heritage and Automatic Caliber L899. Both represent excellent choices in the luxury watch category.
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Specifications Compared
| Feature | Longines Master Collection Moonphase | Seiko Prospex "Turtle" |
|---|---|---|
| Price | ~$3,000 | ~$500 |
| Case Size | 40mm | 45mm |
| Movement | Automatic Caliber L899 | Automatic Caliber 4R36 |
| Caliber Type | Automatic (ETA A31.L91 base) | In-House Automatic Manufacture |
| Power Reserve | 72 Hours | 41 Hours |
| Water Resistance | 30m (3 ATM) | 200m (20 ATM) Diver |
| Crystal | Sapphire Crystal | Sapphire Crystal |
| Case Material | Stainless Steel | Stainless Steel |
| Origin | Swiss Made | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Longines's design language vs Seiko's approach
Movement & Performance
Automatic Caliber L899 vs Automatic Caliber 4R36
Wearability & Fit
40mm vs 45mm — different wrist presence
Value & Cost of Ownership
Seiko is $2,500 more affordable
Water Resistance
30m (3 ATM) vs 200m (20 ATM) Diver
Our Verdict
Longines
Master Collection Moonphase
Choose the Longines Master Collection Moonphase if you prioritize Automatic (ETA A31.L91 base) engineering, Swiss Made craftsmanship, and 30m (3 ATM) water resistance. At ~$3,000, it delivers Automatic Caliber L899 with 72 Hours power reserve.
Check Price on AmazonSeiko
Prospex "Turtle"
Choose the Seiko Prospex "Turtle" if you value In-House Automatic Manufacture technology, Made in Japan heritage, and 45mm proportions. At ~$500, the Automatic Caliber 4R36 with 41 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Longines Master Collection Moonphase and Seiko Prospex "Turtle" represent two distinct approaches to fine watchmaking — the Longines bringing Swiss Made tradition while Seiko delivers Made in Japan engineering.
Frequently Asked Questions
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