The black Citizen Promaster Dive EO2020-08E is a compact-format dive watch with a 36.5 mm case width on Citizen’s US page (rounded to 37 mm by Citizen Italy), an 18 mm lug width, light-powered Eco-Drive movement and a manufacturer-rated 200 m water resistance. Its diameter sounds small beside many dive watches, but the bezel takes up visual space that makes the dial look smaller still. That proportion—not the case measurement alone—is the key to deciding whether its size will suit you.
Is the Citizen Promaster Dive 37mm too small?
Not necessarily. Citizen lists the black EO2020-08E at 36.5 mm wide in the United States; its Italian page rounds the same reference to 37 mm. Those figures describe the case, not how large the watch looks on the wrist. The rotating dive bezel occupies part of the watch’s face, leaving less visible dial than the diameter alone might lead you to expect.
In a June 23, 2023 hands-on account of the blue 37 mm sibling, Hodinkee’s Danny Milton observed: “The 37mm riff on the known Citizen dive watch is not better or worse than its larger predecessor – it’s different in a surprising way.” He also found that the bezel-to-dial proportions made the dial seem smaller than expected. That is one reviewer’s impression of the blue model, useful context for the shared format but not a direct assessment of the black EO2020-08E or a universal sizing verdict. Read the Hodinkee hands-on account.
If you prefer a restrained case size but want a watch face that reads as broad and open, the bezel-heavy design may not be your preference. If you like compact watches and the functional look of a dive bezel, 36.5–37 mm is a meaningful case measurement to consider alongside the dial proportion.
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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.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 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.
How does the EO2020-08E wear?
There is no direct wear assessment of the black EO2020-08E here. The closest published impression is Milton’s report on the blue sibling, which he described as feeling familiar on the wrist. Treat that as an editorial impression of a related version, not a promise about fit: wrist shape, strap adjustment and personal preference all affect how a watch feels.
For a more useful fit check than diameter alone, compare the watch’s case width and overall outline with a watch you already wear comfortably, and consider whether you like the bezel’s visual share of the face. The supplied specifications establish an 18 mm lug width, but do not give a lug-to-lug measurement, so they are not enough to determine how far the case will span your wrist.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 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.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
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- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Is the Citizen EO2020-08E a real dive watch?
Citizen US specifies 200 m/20 bar water resistance and describes the EO2020-08E for scuba diving. Citizen Italy calls it a professional ISO 6425 diver, while Citizen Australia lists ISO diver certification. These are manufacturer descriptions and specifications; they are not an independent test of a particular watch.
Regional Citizen pages list a one-way rotating bezel and screw-down crown; Italy also specifies a screw-fastened caseback. The US page identifies luminous hands and markers, while Australia lists a low-charge indicator. Taken together, the published features suit the watch’s stated dive-watch purpose, but anyone planning to use it underwater should follow the watch’s instructions and have its water resistance maintained appropriately.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Movement, power reserve and everyday specifications
The watch uses Citizen’s E168 Eco-Drive movement. Citizen describes Eco-Drive as powered by light, eliminating the need for battery replacement. Citizen Italy states a 180-day power reserve; Citizen Australia describes the reserve as six months. The US product listing confirms the movement but does not state a reserve figure.
| Specification | What Citizen lists |
|---|---|
| Reference and dial | EO2020-08E; black dial (Citizen US) |
| Case width | 36.5 mm (Citizen US); 37 mm (Citizen Italy) |
| Movement | E168 Eco-Drive, light-powered (Citizen US and Italy) |
| Power reserve | 180 days (Citizen Italy); six months (Citizen Australia) |
| Water resistance | 200 m/20 bar (Citizen US); 20 bar (Citizen Italy); 200 m (Citizen Australia) |
| Case and crystal | Stainless steel case; mineral crystal (Citizen US). Italy lists mineral glass. |
| Strap and lug width | Black polyurethane strap; 18 mm lug width (Citizen US). Italy describes a rubber strap. |
| Functions | Three hands and date (Citizen US); Australia also lists a low-charge indicator. |
Sources: Citizen Watch US, Citizen Italy, and Citizen Australia. Regional pages use slightly different wording and rounding; the table preserves those distinctions rather than treating them as separate watch variants.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
What strap size does the Citizen Promaster 37mm use?
Citizen US lists an 18 mm lug width for the EO2020-08E, which is the relevant starting point when considering another strap. The supplied watch comes on a black polyurethane strap; Citizen Italy describes it as rubber. A third-party 18 mm strap still needs to fit the case’s lug shape and attachment, and should be suitable for the activity and water exposure you intend. Citizen’s specification does not mean a replacement strap is required.
Is the EO2020-08E still available?
Citizen’s US product page showed the EO2020-08E as sold out when checked on October 4, 2026. That is a time-sensitive US stock status, not evidence that Citizen has discontinued the model or that it is unavailable in other markets. Check Citizen’s current regional listing or retailer stock before buying; confirm the seller, market and exact reference number.
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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.
Who should consider this watch?
The EO2020-08E makes the most sense for someone drawn to a compact stainless-steel dive-watch format, light-powered movement and an explicitly stated 200 m rating. Its 18 mm lug width offers a defined starting point for strap options, while the bezel-heavy face is a design choice to assess visually rather than infer from case diameter alone. The available evidence does not establish a current competitor comparison or price basis for calling it the best choice or a value leader.
Hodinkee’s collection overview lists the black EO2020-08E alongside blue and pink 37 mm siblings, and identifies the collection’s 200 m rating, date window, elapsed-time bezel and rubber strap. See the collection overview.
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