Citizen Promaster Fujitsubo Mechanical Diver (NB6021, Series 8 GMT). Current Prices, JDM Listings, Market Analysis
The Citizen Promaster Fujitsubo Mechanical Diver is a JDM diver from Citizen's Promaster line, distinguished by the Series 8 GMT complication that sets it apart from the broader Promaster catalog. Tonbo tracks this reference because the US-Japan price spread has historically generated actionable margins for buyers sourcing directly from Japan. At a current US median of $425, the NB6021 sits in a tier where careful sourcing discipline pays off. The GMT complication adds both appeal and pricing complexity, which is why this model stays on the active watchlist.
Current US Market Value
The Citizen Promaster Fujitsubo Mechanical Diver NB6021 price currently sits at a US median of $425, based on 52 verified comps pulled from eBay sales data. The interquartile range runs from $345 at the 25th percentile to $534 at the 75th percentile, a spread wide enough to suggest meaningful condition variance in the secondary market. That $189 spread between the bottom and top of the middle half is worth noting when evaluating any individual listing. Comp quality on this model is rated green, meaning the underlying sales data meets Tonbo's verification threshold and the median figure reflects real closed transactions rather than asking prices.
Active JDM Listings
Japan is currently showing active inventory on the NB6021, with six listings surfaced on Yahoo Shop within the past two weeks. Pricing spans a wide range, from the lower end around ¥62,800 to highs above ¥115,000, which reflects the typical mix of condition grades and seller types you find across Japanese platforms. At current exchange rates, the lower end of that range lands meaningfully below the US market median, which is what drives alert activity on this reference.
- ¥62,800 on Yahoo Shop (Jun 11)
- ¥69,800 on Yahoo Shop (Jun 11)
- ¥80,900 on Yahoo Shop (Jun 11)
- ¥100,100 on Yahoo Shop (Jun 11)
- ¥114,400 on Yahoo Shop (Jun 11)
Condition details on these listings are currently unclassified in the data, so buyers should verify grade and box or paper status before committing to any purchase. If you want to buy NB6021 from Japan, that due diligence step is where most of the sourcing risk lives.
Recent Alert History
The NB6021 has fired twice in the past 90 days on Tonbo's signal system, which indicates consistent deal flow rather than a one-off event. The more recent trigger came on May 23 at the opportunity tier, with a landed cost of $539 against a US median of $683 at the time, representing approximately 21% gross margin before selling fees. The earlier alert on May 18 was a strict tier signal, a higher-confidence flag, with a landed cost of $476 against a US median of $761, producing roughly 37% gross margin. Both signals suggest that when favorable listings appear, the gap between Japan acquisition cost and US resale value has been material. You can review the full signal methodology at tonbomarket.com/signals.
Japan vs. US Price Gap
The NB6021 price gap between Japan and the US is driven by the usual JDM dynamics: domestic Japanese supply is relatively liquid, demand is more diffuse, and the watch does not carry the same collector premium in its home market that it earns among GMT diver enthusiasts in North America. The Series 8 GMT complication is the primary value driver in the US, where complication-equipped divers from Japanese manufacturers tend to hold a stronger floor than comparable time-only pieces. The main risk factor here is the GMT complication itself. Complications introduce more potential failure points, and a GMT module that needs service can meaningfully erode margin, so verifying function before purchase is not optional on this reference. Buyers sourcing NB6021 for sale listings in Japan should treat any listing without a confirmed working GMT hand as a condition-grade question, not a price question.
Track Citizen Promaster Fujitsubo Mechanical Diver on Tonbo
Tonbo's Collector tier is free to start at tonbomarket.com/dashboard and includes a five-model watchlist with no credit card required. Adding the NB6021 to your list means Tonbo monitors Japan listings and US comps continuously, surfacing the kind of gap data shown above without manual searching. Member tier at $10 per month adds real-time Discord alerts when the model fires a strict or opportunity signal, which is how the May alerts above reached subscribers within hours of a qualifying listing appearing. If the NB6021 is already on your radar, the free tier is the right starting point. If you want first-mover timing on deals, the alert layer is where that edge comes from. You can also browse current active opportunities across the full catalog at tonbomarket.com/deals.