Seizaiken SEIKO 364 SR621SW Silver Oxide Watch Battery

Precise timekeeping requires a precise energy source – the Seizaiken / SEIKO 364 SR621SW silver oxide watch battery delivers a stable 1.55V voltage for high-quality wristwatches and precision instruments. This compact button cell, measuring 6.8mm in diameter and 2.2mm in height, is ideal for elegant men's and women's watches, small quartz movements, and other precision applications where reliability in a confined space is essential.

As a brand of Seiko Instruments, Seizaiken batteries are 100% manufactured in Japan and are trusted by watchmakers and service centers worldwide for their high long-term stability, leak-proof design, and consistent voltage curve. The silver oxide chemistry ensures more consistent performance and longer runtimes than alkaline batteries – ideal for watches intended to run reliably for years. With numerous compatibility designations, this battery replaces many common 364/SR621SW/AG1 types, making it a flexible professional solution for workshops and end users.

Key features:

• Seizaiken / SEIKO 364 SR621SW Silver Oxide Watch Battery, 1 piece in blister pack

• Chemistry: Silver oxide – stable voltage and long runtime for watches

• Nominal voltage: 1.55V – constant supply for precise quartz movements

• Dimensions: Diameter 6.8 mm, Height 2.2 mm – Standard size SR621SW/364

• Made in Japan – Seiko Instruments quality manufacturing

• High reliability and very good leak protection thanks to optimized sealing.

• Specifically designed for watches – suitable for analog and digital models

• Universally applicable in small electronics such as watches, mini-tools and measuring instruments

• 0% mercury – modern, environmentally conscious silver oxide technology

• Original Seizaiken / Seiko brand product – valued by watchmakers worldwide

Advantages & Applications:

• Ideal for wristwatches, pocket watches, small quartz movements and specialty watches.

• Can be used in other small devices such as mini-timers, thermometers and measuring instruments.

• Long operating time and stable voltage for precise timekeeping over many months

• Japanese manufacturing quality – preferred by professional watchmakers

• Direct replacement for many 364/SR621SW/AG1/G1 batteries – high compatibility

• Suitable for low to medium load profiles in watches and delicate electronics

• Safe storage and long shelf life without leakage

• Reliable performance in luxury and designer watches

• Saves on costly watch repairs due to long operating life