The Citizen Promaster NB6021-17E stands out as a prime example of how dive watches can blend rugged function with sleek aesthetics. As part of the respected Citizen Promaster line, this model is engineered for professional divers but appeals equally to enthusiasts who appreciate a high-performance tool watch. Its robust construction, refined detailing, and ISO-certified dive capabilities position it as a reliable companion both underwater and on land. With a design inspired by vintage Citizen Dive watches of the 1970s, the NB6021-17E pays tribute to heritage while utilizing modern materials and technologies.

Crafted from Super Titanium™ using Citizen's proprietary Duratect surface hardening technology, the NB6021-17E is remarkably lightweight yet incredibly strong. This material choice not only enhances durability but also ensures greater comfort during long-term wear. Unlike heavier stainless steel models, this dive watch wears effortlessly, even during extended underwater excursions or all-day urban adventures. For fans of Citizen Eco Drive Titanium, this model offers a similar lightweight strength but uses a mechanical movement, appealing to purists who appreciate automatic watchmaking.

At the heart of the NB6021-17E is Citizen's in-house Caliber 9051 automatic movement, which offers 42 hours of power reserve and a frequency of 28,800 vibrations per hour. This high-beat movement ensures precision and smoother sweep of the second hand. Unlike the solar-powered Citizen Eco Drive models, this watch celebrates traditional mechanical engineering. For those familiar with Citizen Automatic collections, this timepiece presents a refined execution that balances technical mastery with vintage soul. The movement is protected by an anti-magnetic case, designed to keep accuracy intact even in challenging environments.

The watch features a clean, highly legible dial with bold markers and thick hands, all coated with long-lasting lume for optimal visibility in low-light conditions. The black dial contrasts beautifully with the white indices, and the orange minute hand adds a pop of color—subtle, yet useful for divers tracking their bottom time. The unidirectional bezel rotates with satisfying resistance, further emphasizing its function-first ethos. Designed for diving depths up to 200 meters, the NB6021-17E meets ISO 6425 standards and includes a screw-down crown and case back for enhanced water resistance.

While it is crafted as a professional tool, the NB6021-17E also serves as a compelling everyday watch. Its dimensions—41mm in diameter and just 12mm thick—strike the right balance between wrist presence and wearability. The supplied polyurethane strap is soft and flexible, built for underwater reliability but comfortable enough for daily wear. Whether paired with casual attire or outdoor gear, the watch adapts to any setting with ease. It offers an appealing alternative to more tech-forward models like Citizen Satellite Wave GPS or Citizen Smartwatch, providing timeless charm with mechanical sophistication.

Though designed with men in mind, this timepiece is also suitable for individuals seeking a rugged, mid-sized dive watch with authentic functionality. In a growing market of oversized tool watches, the Promaster NB6021-17E stands out for its proportionate build. Those who typically explore Citizen watches for women may find this model a great unisex option if they're drawn to purpose-driven design with genuine capability.

This watch is also a celebration of Citizen's dive heritage. From the legendary Aqualand to more recent releases in the Citizen Promaster and Citizen Dive categories, the brand has consistently delivered watches that combine professional-grade performance with thoughtful aesthetics. The NB6021-17E continues this legacy, refined through decades of experience and customer feedback. It captures what makes mechanical dive watches so captivating—their ability to perform in extreme environments while still offering timeless appeal on land.

Collectors and enthusiasts will appreciate the NB6021-17E for its focused execution, traditional movement, and titanium build. It doesn't try to overextend with unnecessary features but delivers where it matters: legibility, durability, and comfort. For those who are fans of Citizen Automatic pieces, or those transitioning from solar-powered models like the Citizen Eco Drive, this is an opportunity to explore the charm of mechanical timekeeping. It's a watch that feels purpose-built yet universally wearable, balancing utility with understated sophistication.