The Tool Desk
Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →The Citizen Promaster Nighthawk BJ7138-04E pairs a B877 Eco-Drive movement with a second-time display, date and pilot-style slide-rule markings. Its 42 mm case and 21.97 mm lugs make it a substantial watch on paper; whether that size, the dial layout and its leather strap work for you depends on your wrist and priorities. This is a specification- and owner-feedback-based review, not a hands-on test.
What the BJ7138-04E offers
The exact reference is BJ7138-04E. Citizen US and Canada list the B877 Eco-Drive movement, black dial, mineral crystal, leather strap, date and dual time. The dial also includes a 24-hour display and a register ring marked as an airline slide rule. Those features make it a function-heavy analog watch, rather than a digital calculator; consult the B877 manual for instructions on operating the movement and reading its scales.
Citizen describes Eco-Drive as converting light—from bright sunlight to dim indoor lighting—into energy for the watch. Citizen Middle East lists a six-month power reserve for this regional product specification, as well as an insufficient-charge warning and overcharge prevention. That reserve is a manufacturer-stated figure, not an independent runtime test. Citizen US product page; Citizen Canada product page; Citizen B877 manual; Citizen Eco-Drive explanation; Citizen Middle East product information.
Specifications and regional differences
| Specification | Citizen-listed information |
|---|---|
| Movement | B877 Eco-Drive, listed by Citizen US and Canada |
| Case width | 42 mm, listed by Citizen US and Canada |
| Lug width | 21.97 mm, listed by Citizen US and Canada |
| Weight | 89.3 g, listed on Citizen Canada |
| Dial and crystal | Black dial and mineral crystal, listed by Citizen US and Canada |
| Strap | Leather strap; Citizen Canada also specifies a buckle |
| Functions | Date and dual time, listed by Citizen US and Canada; the regional Middle East page also specifies a 24-hour display |
| Water resistance | Citizen US lists 20 bar/200 m/666 ft and describes the watch for swimming, showering and snorkeling. Citizen Canada lists WR200/20 bar (660 ft). The pages differ on the feet conversion and use wording. |
| Power reserve | Six months, according to Citizen Middle East regional product information; not an independently verified runtime |
Regional pages are not perfectly aligned, so use the rating and activity guidance published for your market rather than combining the feet conversions into a single figure. Water-resistance ratings also describe a watch specification, not a guarantee that an older or poorly maintained example remains sealed.
#1 Best Overall
- Modern, pilot-inspired Promaster timepieces equipped for professional use to discover the world from high above.
- Dual Time (Second Time Zone), Date
- Silver-Tone Stainless Steel
- Luminous Hands and Markers, Anti-Reflective Mineral Crystal
- Sustainably powered by any light, with our Eco-Drive technology this watch never needs a battery. 200 Meters Water Resistant and 5 Year Limited Warranty.
Size, legibility and owner impressions
The listed 42 mm width gives a useful starting point for fit, while the Canadian listing’s 89.3 g weight gives a sense of the watch’s stated mass. Neither figure predicts how it will sit on an individual wrist. The register markings and multiple time displays add information to the dial; buyers who prioritize an uncluttered face or an immediately obvious date should inspect clear photographs or try the watch in person where possible.
Customer reviews hosted by Citizen Canada are mixed individual impressions, not representative testing. Some reviewers praise the appearance, versatility, timekeeping or perceived lume; one low-rated reviewer criticized comfort, date legibility and lume visibility. Verified buyer Sean, in a review dated May 31, 2023, wrote: “Love it for work since we do our paperwork in UTC.” That is one owner’s account of a specific use, not a performance guarantee. Citizen’s own description calls the design inspired by the sleek lines of a stealth helicopter; that is manufacturer marketing, not an independent design assessment.
Rank #2
- Citizen Men's Eco-Drive Promaster Eco Nighthawk Watch, Stainless Steel, Black Polyurethane Strap, Gray Dial, Dual Time, Date (Model: BJ7004-43H)
- Dual Time (Second Time Zone), Date
- Silver-Tone Stainless Steel
- Mineral Crystal
- 200M Water Resistant and 5 Year Limited Warranty
Setting the dual time and using the slide-rule ring
The B877 manual is the appropriate source for setting and operating this model’s movement. Citizen’s support library can be searched by product or movement number, and Citizen says the movement number is the first four characters of the case number. Use the manual’s instructions rather than assuming how to set the second-time display or interpret a slide-rule scale from the markings alone.
- Open Citizen’s support library and search for B877 or the watch’s product information.
- Confirm that the manual matches the B877 movement before following its setting instructions.
- Use the manual to identify the crown positions and the procedure for adjusting the dual-time display, date and register ring.
Strap replacement and availability
Citizen lists a 21.97 mm lug width, so searching for a nominal 22 mm strap is a reasonable starting point. It is not a universal-fit guarantee: confirm the exact end fit, spring-bar arrangement, strap length and material before ordering.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsRank #3
- Modern, pilot-inspired Promaster timepieces equipped for professional use to discover the world from high above.
- Atomic Timekeeping Technology with Synchronized Time Adjustment Available in 43 World Cities, 1/100 Second Chronograph Measures up to 24 Hours, Perpetual Calendar, Dual Time (Second Time Zone), Power Reserve Indicator
- Black Ion-Plated Stainless Steel with Black Silicone Strap
- Black Dial with Orange and White Accents, Anti-Reflective Mineral Crystal
- Featuring our Eco-Drive technology – powered by light, any light. 200 Meters Water Resistant and 5 Year Limited Warranty
Availability depends on region and date. At the time reflected by Citizen’s cited pages, the US listing showed “Sold Out” and the Canadian listing showed “Discontinued.” Those statuses do not establish that the watch is discontinued worldwide or unavailable from every seller. Check current listings and confirm the reference, condition, return terms and any applicable warranty before buying.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Who should consider the BJ7138-04E?
It is worth considering if you want an analog Eco-Drive watch with a second-time display, date and aviation-style register markings, and you are comfortable evaluating a 42 mm case and a visually busy dial. The main uncertainties for an individual buyer are wrist fit, the practical legibility of the date and markings, and the condition and availability of the particular example. There is not enough comparative evidence here to name a best alternative model.
Quick Recap
Rank #4
- Advanced technology with a deeply iconic look, the latest Promaster Skyhawk A-T reaches a higher altitude in style.
- Designed with a two-tone stainless steel case and gray dial with luminous hand and encased in sapphire crystal, this exceptional timepiece includes atomic time clock synchronization for superior accuracy, time adjustment available in 43 world cities, 1/100 second chronograph measures up to 24 hours, a perpetual calendar, 2 alarms, 99-minute countdown timer, digital backlight display, Universal Coordinated Time (UTC) display, and a power reserve indicator.
- The brown leather strap fastens with a buckle closure.
- This distinctive sports watch utilizes our Eco-Drive technology that’s sustainably powered by light and never needs a battery and is water resistant up to 200 meters.
- Caliber U680.
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.
