The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →The Citizen Promaster NB6021 is a 200 m mechanical diver with a titanium case, Caliber 9051 and a design inspired by Citizen’s 1977 Challenge Diver. It was announced in March 2022 for a summer 2022 release, so “new” describes the original launch—not a 2026 debut. The exact reference matters: NB6021-17E has a urethane strap, while NB6021-68L is the bracelet version.
What is the Citizen NB6021?
The NB6021 is a Promaster mechanical diver associated with the “Fujitsubo,” or barnacle, nickname. Citizen presents it as a modern evolution of its 1977 Challenge Diver. The two official references covered here are NB6021-17E and NB6021-68L; confirm the reference on a listing because their band configurations differ.
Citizen says the design draws on a Challenge Diver found on Sydney’s Long Reef Beach in 1983, six years after its release. The watch was still operating after being covered in barnacles, according to Citizen’s account. That story is the source of the Fujitsubo association; it should not be read as a claim that the NB6021 itself was recovered there.
NB6021-17E specifications
The following figures are from Citizen Japan’s official NB6021-17E product page. Accuracy, price and availability are qualified below because they depend on how and where the watch is assessed or sold.
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- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
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- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
| Specification | NB6021-17E |
|---|---|
| Movement | Citizen Cal. 9051; mechanical automatic and hand winding |
| Power reserve | Approximately 42 hours when fully wound |
| Stated accuracy | Average daily rate of -10 to +20 seconds in static conditions |
| Case width | 41.0 mm |
| Thickness | 12.3 mm |
| Weight | 75 g |
| Case material | Super Titanium |
| Band | Urethane; 20 mm band width |
| Crystal | Sapphire glass |
| Water resistance | 200 m diver water resistance |
| Other listed features | Second-class magnetic resistance, luminous hands and indices, unidirectional bezel and screw-lock crown |
How accurate is Caliber 9051?
Citizen lists an average daily accuracy of -10 to +20 seconds, measured in a stationary position. The company cautions that the rate during wear may fall outside that range depending on wearing time, the watch’s position, wrist movement and winding. Treat the figure as Citizen’s stated static-condition specification, not a guarantee of the result on every wrist.
What does its magnetic resistance mean?
Citizen lists the 9051 as having second-class magnetic resistance and says the movement uses anti-magnetic materials in the hairspring and other components. This is enhanced resistance, not immunity to magnetic fields or a promise that the watch can never be affected. The cited descriptions do not establish protection from every source or exposure.
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- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
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Is the NB6021 suitable for diving?
Citizen Japan lists 200 m diver water resistance and says the watch clears ISO requirements. Citizen’s US product page describes the rating as “200M/20Bar [Scuba Diving]” and specifies an anti-reflective sapphire crystal. A water-resistance rating alone does not establish that a particular watch is safe to use on a dive: condition, maintenance and the manufacturer’s operating guidance also matter.
NB6021-17E vs. NB6021-68L
| Reference | Band configuration | Other confirmed distinction |
|---|---|---|
| NB6021-17E | Urethane strap | Citizen Japan lists a black dial; listed Japan price is ¥115,500 |
| NB6021-68L | Bracelet | Citizen’s 2022 announcement identifies the bracelet configuration; a comparable current Japan price is not stated in the cited product information |
Both references are part of Citizen’s NB6021 launch family. The confirmed distinction here is the band configuration; check the exact reference and market listing for any further dial or finish details. A bracelet may suit someone who prefers an integrated metal band, while the 17E’s urethane strap gives a different wearing setup. The cited official material does not provide a comparative wear test or establish which is more comfortable.
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- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Price and availability
Citizen Japan lists ¥115,500 for the NB6021-17E and notes that it may be unavailable. That is a regional listed price, not a universal current price or a survey of retailer pricing. Stock and pricing can vary by country and seller, so verify both against the exact reference before buying.
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- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
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What to check before buying
- Reference: Make sure the listing says NB6021-17E or NB6021-68L; the strap and bracelet versions are not interchangeable descriptions.
- Seller and region: Confirm who is selling the watch, whether the listing is for your market, and whether stock is current.
- Fit and wearing preference: Compare the listed 41.0 mm width, 12.3 mm thickness and 75 g weight for the 17E with your own preferences. These measurements do not predict how every wearer will find the watch.
- Dive use: Check the watch’s condition and follow Citizen’s guidance; the stated rating is not a substitute for inspection or maintenance.
- Like-for-like comparisons: When comparing other divers, weigh case dimensions and weight, movement and reserve, the conditions attached to accuracy figures, water resistance, magnetic resistance, crystal, band, service support and local price.
Sources
- Citizen Japan: NB6021-17E product specifications, price and availability note
- Citizen: March 2022 NB6021 launch announcement
- Citizen US: NB6021-17E product description
- Citizen global Promaster: Challenge Diver history and Cal. 9051 description
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
