The Seiko Presage Sharp Edge collection, which made its debut just three years ago in 2020, has quickly become a crowd favourite for several simple and good reasons – it offers design features that resemble Grand Seiko, such as the faceted case and patterned dial, all for around $1,000.

Naturally, the collection has grown to include a range of practical features, including a GMT, but one model – the open-heart version, has a more limited appeal. Thankfully, Seiko has just unveiled the new Sharp Edge “Open Heart” models, the SPB415 and SBP417, which feature a smartly tweaked opening for the balance, resulting in a more sophisticated look.

The Low-Down

Seiko has introduced two new references, the SPB415 with a white dial and the SPB417 with a blue dial. Both models feature the familiar Sharp Edge case with its wide, faceted lugs. However, upon closer inspection, you’ll notice that the latest cases are more nuanced, featuring a polished bevel that runs along the case flank. This elegant detail contrasts beautifully with the bold, large brushed lugs and sets these models apart from most other Sharp Edge watches.

But, of course, the highlight of the latest duo is the dial, or more precisely, the opening of the dial. Rather than the typical open-heart design that exposes the entire balance wheel, Seiko has incorporated a skeletonized frame with the asanoha (Japanese for “hemp leaf”) pattern found on the dial. This unique approach results in a more refined open-heart design that maintains the overall completeness of the dial from a distance, while still providing a glimpse of the moving balance upon further scrutiny.

Notably, the bridges revealed through the opening have been finished thoughtfully to match the upscale look and quality of the rest of the timepiece. In contrast to most “open-heart” watches at this price point, which usually have basic finishing with exposed rough circular graining around the balance, Seiko has employed brushing and polishing to achieve a clean and precise appearance. In fact, Seiko takes pride in the finishing, even shaping the skeleton dial above the opening with a circle at the bottom right to highlight the parts.

Beating away inside the watch is the new cal. 6R5J movement, which boasts a three-day power reserve – two hours more than the 6R35 found in the basic time-and-date Sharp Edge models. It also includes a 24-hour indicator at six o’clock, allowing for easy differentiation between day and night when changing dates.

IMHO

Open-heart watches are often criticised for their bland presentation of the balance, which can look out of place against the dial if the movement is not nicely finished. However, the latest design from Seiko takes a more subtle approach. The additional framing above the opening is a design feature that echoes the dial, and the parts that are revealed are nicely finished, adding to the watch’s overall attractiveness and giving it a handsome look that is well-suited for its price tag of $1,200.

Tech Specs

Seiko Presage Sharp Edge “Open Heart”

Movement: cal. 6R5J; automatic; 72 hours power reserve
Functions: Hours, minutes, seconds, and 24-hour indicator
Case: 40.2 x 13.5 mm; steel; water resistant to 100 m
Strap: Steel bracelet
Price: USD 1,200