CITIZEN PROMASTER EO2021-05L Eco-Drive Diver 200m ISO Blue Dial 37mm Boys Size

The CITIZEN PROMASTER EO2021-05L is a professional-grade diver’s watch that combines rugged performance with a versatile 37mm case size. Designed as a boys-size model within the PROMASTER diver lineup, it offers a balanced fit that suits slimmer wrists while maintaining full-scale diving capability. It is also an excellent option as a pair watch.

Built to ISO standards for diving watches, this model features 200-meter water resistance suitable for recreational scuba diving. Safety-focused details include a unidirectional rotating bezel to prevent accidental time extension, a screw-lock crown for enhanced water resistance, and luminous hands and indexes for high visibility underwater or in low-light environments. Magnetic resistance (Class 1) further supports reliable performance in demanding conditions.

Powered by CITIZEN’s Eco-Drive technology (Caliber E168), the watch converts light into energy, eliminating the need for regular battery replacement. Once fully charged, it operates for approximately six months without additional light exposure. When radio signals are not involved, it maintains an accuracy of ±15 seconds per month.

The stainless steel case is paired with a durable blue urethane strap designed for comfort and flexibility during active use. A crystal glass protects the dial, while the bold blue color scheme enhances its sporty character both in and out of the water.

Key Specifications Display type: Analog Movement: Japanese quartz (Eco-Drive solar-powered, Caliber E168) Accuracy: ±15 seconds per month Power reserve: Approximately 6 months on full charge Water resistance: 200 meters (ISO-certified diver’s watch) Case material: Stainless steel Band material: Urethane Band color: Blue Dial color: Blue Case diameter: Approximately 37mm Glass: Crystal glass Clasp: Buckle Functions: Unidirectional rotating bezel, screw-lock crown, luminous hands and indexes, magnetic resistance Class 1

The CITIZEN PROMASTER EO2021-05L delivers authentic diver performance in a compact and highly wearable size. Combining ISO-certified durability, solar-powered convenience, and bold sport styling, it is a dependable companion for underwater adventures and everyday active lifestyles alike.