The Seiko Prospex SPB321J1, affectionately known as the ‘Sumo’ by Seiko fans, is a bold and powerful diver’s watch recognised for its substantial size, strong case shape and distinctive 12 o’clock marker. Its commanding presence reflects the durability and confidence expected from a professional-grade timepiece.
This latest evolution of the Sumo design introduces modern enhancements, including a ceramic bezel and a super-hard coating on both the case and bracelet for increased durability. A newly developed three-row bracelet and updated clasp improve comfort and wearability, while the blue dial features a finely pressed pattern with graduated tones for added depth and visual impact.
Prospex is a combination of the words ‘Professional’ and ‘Specifications’, representing Seiko’s dedication to creating watches that are practical, reliable and built for demanding environments. Since launching Japan’s first diver’s watch in 1965, Seiko has continued to set global standards in dive watch innovation, with the SPB321J1 proudly carrying this legacy forward.
