Seiko Prospex SPB143
SPB143
- Case
- 40.5mm
- MSRP
- $1,200
- Movement
- Automatic
- Reserve
- 70h
VS
Building 1v1 comparison
Building 1v1 comparison
1v1 Watch Comparison
A focused side-by-side page for specs, fit, movement details, review notes, and enthusiast context.
SPB143
L3.779.4.56.6
Pair Review
Built from the saved specs and wearability notes for these two watches, then weighed against enthusiast priorities like fit, movement quality, practicality, finishing, value, and collector appeal.
Where it wins
Collectors who prefer restrained, vintage-inspired design and classic dive-watch proportions
Where it wins
Buyers prioritizing technical refinement and a more premium spec sheet
The Longines uses the automatic L888.5 with a 72-hour power reserve and a 3.5 Hz / 25,200 vph beat rate, plus the wearability notes specifically call out a silicon balance spring and a more technical, upscale feel. The Seiko uses the automatic 6R35 with a 70-hour power reserve, which is also strong for daily practicality, but no listed frequency or anti-magnetic tech is provided here. On the supplied data, Longines has the clearer technical edge; Seiko remains the simpler, proven option. Winner: Longines
The Longines is 39mm in diameter, 11.7mm thick, 48.1mm lug-to-lug, and 167g, while the Seiko is 40.5mm wide, 13.2mm thick, 47.6mm lug-to-lug, and 180g. In practice, the Longines should feel slimmer, lighter, and more compact, especially given the wearability note that it wears noticeably smaller than most 39–41mm divers and benefits from a strong tapered bracelet and tool-less micro-adjust clasp. The Seiko has the slightly shorter lug-to-lug, but its extra thickness and weight will make it sit more substantial on wrist; its notes describe excellent balance and compactness for a dive watch, though with a more basic clasp. For smaller wrists or those who prefer a sleeker profile, the Longines has the edge; for buyers who like a slightly more substantial vintage-style diver, the Seiko is still very wearable. Winner: Longines
The Longines offers a black lacquered polished dial, applied indexes with Swiss Super-LumiNova, sapphire crystal with anti-reflective coating on both sides, a ceramic bezel, 300m water resistance, date display, and a refined steel bracelet with double-security clasp and micro-adjust system. The Seiko brings a sunburst grey dial, luminous markers, sapphire crystal, 200m water resistance, date display, steel bracelet, and a secure fold clasp. In real-world use, the Longines is the more legible and more premium-feeling package, with stronger lume specification, better bezel and crystal materials, and greater water resistance; the Seiko is versatile and easy to wear, but less fully specified in finishing and adjustment convenience. Winner: Longines
The Seiko’s MSRP is $1,200 versus $2,200 for the Longines, so it enters at a significantly lower price point. The Longines does offer more clearly specified luxury signals in the data — ceramic bezel, double-sided anti-reflective coating, micro-adjust clasp, and a more technically detailed movement note — which help justify the higher MSRP for buyers who care about refinement and execution. The Seiko counters with strong heritage signaling through its Prospex line and 62MAS-inspired wearability notes, plus a lower-cost route into a respected mechanical dive watch. If the question is simple upfront cost and broad practicality, Seiko wins; if it is ownership experience per dollar in terms of finishing and technical spec, Longines has the stronger package but at a higher price. Winner: Seiko
Compared
SPB143
L3.779.4.56.6