Citizen Calendrier BU2021-51L, 44mm, Blue Dial
Citizen Calendrier 44mm, Blue Dial
Citizen BU2021-51L is a men's solar-powered dress watch with a blue dial, 44mm stainless steel case, and 100m water resistance.
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About this item
- Timeless styling that effortlessly takes you from work to play.
- Features 12/24 hour time display and analogue day/date function.
- Crafted with silver-tone stainless steel for durability.
- Equipped with luminous hands and an anti-reflective mineral crystal.
- Offers 100 metres water resistance, suitable for swimming and snorkelling.
- Citizen Eco-Drive technology powers the watch by light, eliminating battery changes.
Top Highlights
- Brand
- Citizen
- Model Name
- Eco-Drive
- Model Number
- BU2021-51L
- Department
- Men
- Item Type
- Watch
- Manufacturer
- Citizen Watch Company
- Country of Origin
- Japan
- First Available
- 20 January 2015
- Release Year
- 2015
Features & Specs
- Display
- Analog
- Movement Type
- Solar
- Calibre
- 8729
- Additional Features
- Anti-Reflective Mineral Crystal, Day/Date, Glow In The Dark
- Complications
- Date, Day, 12/24 hour time
- Battery
- No battery (solar)
- Strap Type
- Bracelet
- Case Material
- Stainless steel
- Case Size
- 44.0 mm
- Case Thickness
- 8.5 mm
- Lug Width
- 23.0 mm
- Weight
- 172.0 g
- Water Resistance
- 100 m
- Sport Type
- Swimming, Snorkeling
- Strap
- Stainless steel
- Clasp
- Push Button Deployment Clasp
- Closure Type
- Fold-over, Push-Button
- Crystal
- Mineral crystal
- Dimensions
- 1.5 x 1.5 x 1.5 cm; 172.08 g
Style
- Style Name
- Watches
- Dial Shape
- Round
- Dial Colour
- Blue
- Band Color
- Silver
- Theme
- Classic
- Face Style
- Sector or Crosshair
- Collection
- Calendrier
- Dial Markers
- Luminous hands, Glow in the dark
Will it fit your wrist?
Best on 18.5–19.5 cm (7.3–7.7 in) wrists
A 44 mm case sits just right on these wrists. If your wrist is 19.5–20.5 cm, it looks smaller and more understated. If your wrist is 17.5–18.5 cm, it looks bigger and bolder.
Measure your wrist and see what fitsA rough guide based on case diameter only.
Is this watch big or small?
61% of the men's watches we list are smaller than this one
The most common men's size is 42 mm (173 models). 140 models are 44 mm, like this one.
All our watch size dataDescription
The Citizen BU2021-51L Eco-Drive Calendrier watch offers a blend of classic aesthetics and modern solar technology, making it an ideal choice for the discerning gentleman seeking reliability and style. Its elegant design, featuring a striking blue dial and robust stainless steel construction, ensures it transitions seamlessly from professional settings to casual outings. This timepiece is designed for those who appreciate functional complications without compromising on sophisticated appeal.
At its core, the BU2021-51L is powered by Citizen's renowned Eco-Drive solar movement, which harnesses any light source to keep the watch running indefinitely, eliminating the need for battery replacements. Encased in a durable 44mm stainless steel case with a mineral crystal, it offers 100 metres of water resistance, providing peace of mind for everyday wear and recreational water activities. The watch also features a day/date display and 12/24 hour time, enhancing its practical utility.
A key highlight is the luminous hands and anti-reflective mineral crystal, ensuring excellent legibility in various lighting conditions. This combination of light-powered convenience, robust build, and useful calendar functions makes the Citizen Eco-Drive Calendrier a versatile companion. It is particularly well-suited for individuals who value a low-maintenance watch that combines classic design with contemporary eco-friendly technology.
Frequently Asked Questions
Is the Citizen BU2021-51L suitable for daily swimming and showering?
The Citizen BU2021-51L offers 100 metres of water resistance, making it suitable for daily swimming and snorkelling. However, it is generally recommended to avoid wearing any watch in the shower due to potential issues with steam and soap affecting the seals over time.
How does the Eco-Drive movement compare to traditional quartz watches?
The Citizen BU2021-51L features an Eco-Drive solar movement, which is a type of quartz movement powered by light. Unlike traditional quartz watches that require periodic battery replacements, Eco-Drive watches continuously recharge, offering a virtually maintenance-free power source and consistent accuracy.
What is the typical wrist size range this 44mm watch would fit?
A 44mm case size like the Citizen BU2021-51L generally fits medium to larger wrists well, typically ranging from 6.5 to 8 inches (16.5 to 20 cm) in circumference. For smaller wrists, it might appear quite prominent, so trying it on is always recommended for optimal comfort and aesthetics.
Does the watch's mineral crystal offer good scratch protection?
The Citizen BU2021-51L is equipped with a mineral crystal, which provides good resistance against everyday bumps and minor scratches. While it is more durable than acrylic, it is not as scratch-resistant as sapphire crystal, which is often found in higher-end timepieces.
What are the main complications offered by the Citizen BU2021-51L?
The Citizen BU2021-51L is designed with practical complications for daily utility. It features an analog day and date display, allowing you to quickly reference the current day of the week and date. Additionally, it includes a 12/24 hour time display for enhanced timekeeping versatility.
Editor's take
The Citizen BU2021-51L Eco-Drive Calendrier represents a compelling proposition for those seeking a reliable and aesthetically pleasing timepiece without the fuss of battery changes. Positioned within Citizen's accessible yet innovative Eco-Drive line, this model caters to individuals who appreciate classic watch design infused with modern, sustainable technology. Its 44mm case size and versatile styling make it suitable for a broad range of wrist sizes and occasions, from daily office wear to weekend leisure.
Technically, the watch shines with its Eco-Drive solar movement, a hallmark of Citizen's commitment to environmental responsibility and user convenience. This light-powered quartz mechanism ensures exceptional accuracy and a virtually maintenance-free experience, as it continuously recharges from any light source. The robust stainless steel construction of both the case and bracelet, paired with a durable mineral crystal, provides a solid foundation for daily wear, while the 100-metre water resistance adds a layer of practical versatility.
While the mineral crystal offers good scratch resistance for most daily activities, it is inherently less scratch-resistant than sapphire, which might be a consideration for those with more demanding lifestyles or who prefer ultimate durability. Furthermore, while the 100m water resistance is ample for swimming and snorkelling, it is not designed for serious diving, lacking the ISO 6425 certification and features of a dedicated dive watch. This watch prioritises everyday elegance and functionality over extreme sport capabilities.
Ultimately, the Citizen BU2021-51L is an excellent choice for someone desiring a handsome, reliable, and eco-conscious daily wearer that offers practical complications like day/date and 12/24 hour time. For those prioritising a more robust crystal or professional diving capabilities, alternatives from Citizen's Promaster line or other brands offering sapphire crystals and higher water resistance might be worth exploring. However, for its intended purpose, this Eco-Drive Calendrier delivers significant value.
In categories
From the manufacturer

Solar Powered Precision
The Citizen Eco-Drive movement eliminates the need for battery replacement. It converts any light source, natural or artificial, into energy, continuously powering the watch. This technology ensures consistent operation and reduces environmental impact.

Robust Construction Details
The 44.0mm stainless steel case provides a substantial presence on the wrist. A mineral crystal protects the dial, offering clear visibility and resilience. With 100 metres of water resistance, this timepiece is suitable for various aquatic activities.
THE DETAILS
Deployment Clasp with Push Buttons

OWN YOUR STYLE- DISCOVER MORE
The Citizen BU2021-51L combines practical functionality with a refined aesthetic suitable for daily wear. Its stainless steel construction, from case to bracelet, offers both durability and a cohesive appearance. This timepiece provides reliable performance without compromising on classic watch design.

CITIZEN PARTNERSHIPS
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