Seiko SRP777 vs SRPE93: Which is the Superior Turtle?

The Seiko Turtle is one of the most recognizable dive watches in the world. It has a storied history, a distinctive design, and a reputation for being both durable and reliable.

So no, the Seiko Turtle isn’t some rare breed of turtle—if that’s what you’re looking for, you might want to check out the National Geographic website instead.

No, this is the nickname given to one of Seiko’s most iconic dive watches, and it’s called the Turtle because of its distinct, cushion-shaped case that resembles a turtle’s shell. 

Seiko first introduced the Turtle back in the 1970s with the legendary 6306 and 6309 models, and since then, the watch has seen multiple reissues, each staying true to its roots while incorporating subtle but necessary modern improvements.

Today, the Seiko Turtle lineup includes a variety of models, all sporting the signature case shape, bold dials with plenty of lume, impressive water resistance, and reliable in-house automatic movements.

While most of these variations have obvious differences, whether it’s case size, dial colors, bezel inserts, or added complications, there are two models that look almost identical: the Seiko Turtle SRP777 and the Seiko Turtle SRPE93. 

If you’re not super familiar with these two watches, you’d be forgiven for struggling to spot any differences between them at all.

Seriously, if you can pick them apart in just a few seconds, you deserve some serious brownie points. But yes, there are subtle differences, and as any watch collector will tell you, even the smallest differences in a watch can have a big impact, whether it’s on how a watch wears, how it looks, or just how it feels on the wrist. 

So today, we’re putting the Seiko Turtle SRP777 and SRPE93 head-to-head, breaking down every little detail, so you’ll know exactly which one is the better choice for you.

The Seiko Turtle SRP777

Starting with the older of the two, the Seiko Prospex Turtle SRP777 is a modern reissue of the legendary Seiko 6309, a famous dive watch that the Japanese watchmaker first launched during the late 1970s.

This modern-day SRP777 reference however arrived in early 2016 but still retained many of the signature Turtle features including the cushion-shaped case, bold dial design, and robust diving capabilities that made its predecessor such a hit. 

At first glance, the SRP777 appears nearly identical to its vintage inspiration, measuring to 44.3mm in diameter with a lug-to-lug of 47.25mm. The stainless steel case features a brushed finish on the top and polished sides, maintaining the classic Seiko diver aesthetic.

Again, it’s the unusual shape of the case that gives the Turtle its nickname with a rounded, ergonomic, and undeniably comfortable profile. Despite its large dimensions, the watch wears smaller than expected due to its short lugs, making it surprisingly wearable on a variety of wrist sizes. 

One of the standout features of the SRP777 is its day-date window. Unlike more modern Seiko divers like the SRPE93, the SRP777 retains a beveled day-date window as a direct homage to the original 6309.

This small yet significant detail enhances the vintage appeal of the watch and is one of the main components that sets it apart from its younger sibling. For collectors and enthusiasts who appreciate the little nuances that make a watch special, this beveling adds a layer of depth and nostalgia. 

The dial is a rich matte black, offering excellent legibility in various lighting conditions. Large, well-defined hour markers are generously coated with Seiko’s proprietary LumiBrite, ensuring that the watch remains highly readable even in low-light environments.

The hands follow a classic Seiko diver design, with a broad arrow-style minute hand and a sword-shaped hour hand, making it easy to distinguish the time at a glance. The seconds hand features a lumed lollipop tip, another nod to traditional Seiko diver aesthetics. 

The bezel is a unidirectional 120-click mechanism with a fully indexed aluminum insert. The action is smooth with firm, precise clicks, making it a joy to operate. Seiko’s bezels are known for their reliability, and the Seiko Turtle SRP777 is no exception, providing an essential tool for divers to monitor elapsed dive times. 

The case back of the SRP777 is another area where Seiko has paid tribute to its past and offers another slight deviation from the SRPE93. The SRP777 features the iconic tsunami wave motif, deeply engraved and prominently displayed, alongside lettering that reads “Air Diver’s 200m”. 

Inside the watch beats Seiko’s in-house 4R36 automatic movement, a workhorse caliber that offers hacking and hand-winding. It also operates at 21,600 vibrations per hour and provides a respectable 41-hour power reserve.

It’s a reliable and robust movement, designed for longevity and ease of maintenance. It’s so reliable that Seiko still uses it in many of the dive watches today. Completing this model is a 22mm black silicone strap that is soft, flexible, and comfortable straight out of the box.

The Seiko Turtle SRPE93

Arriving a little later in 2021, and a watch still in production now, the Seiko Prospex SRPE93, is unsurprisingly another modern take on the Seiko Turtle design.

Much like its predecessors, this model stays true to the core identity of the Seiko Turtle, offering a cushion-shaped case, robust dive watch capabilities, and a timeless aesthetic. 

At 45mm in diameter with a thickness of 13.42mm, the Turtle SRPE93 is slightly larger than the SRP777 but still retains an ergonomic and well-balanced profile on the wrist.

Thanks to its rounded case and relatively short lug-to-lug length, the watch again wears smaller than its dimensions might suggest, making it comfortable for a wide range of wrist sizes. The case is engineered from classic stainless steel and features a brushed finish on the top with polished sides. 

The dial of the Seiko Prospex Turtle SRPE93 is also deep matte black, ensuring excellent contrast and legibility. At the centre are the same large and highly visible hour markers coated with Seiko’s LumiBrite. But peeking out just to the right of the dial is one of the subtle but notable differences between this model and the Turtle SRP777. 

Here you can see the addition of a lume block at the 3 o’clock marker. This lume pip was added to retain the ISO certification, as it is part of the new requirement.

In addition, to accommodate this change, the Seiko Turtle SRPE93 does not have the beveling on the day/date window that was present on the SRP777.

Another update lies in the case back. While it still features the iconic tsunami wave motif, the text has been updated to again reflect the new ISO diving specifications. Instead of the previous “Air Diver’s 200m” marking found on the SRP777, the case back of the Turtle SRPE93 now reads “Diver’s Watch 200m.”

This subtle change may go unnoticed by casual observers, but for Seiko enthusiasts, it represents an important update that aligns with modern dive watch standards. 

Other than that, the SRPE93 retains all the same spec as its older sibling. It has the same unidirectional rotating black aluminium bezel, Seiko’s reliable in-house 4R36 automatic movement with a 41-hour power reserve and a comfortable black silicone strap, secured with a pin buckle.

Seiko SRP777 vs SRPE93 – How to Choose 

The Case Size 

While both watches share the signature Seiko Turtle design, the SRPE93 comes in slightly larger at 45mm compared to the SRP777’s 44.3mm diameter.

The difference might seem minimal on paper, but on the wrist, even a fraction of a millimeter can impact the overall feel. The SRP777’s more compact dimensions make it a great option for those who prefer a slightly more manageable fit without sacrificing the iconic cushion-shaped case.

On the other hand, if you like the presence of a slightly larger case, the SRPE93 will give you that extra bit of wrist real estate while maintaining excellent wearability thanks to the short lug-to-lug distance. 

The 3 o’clock Lume 

One of the most notable updates in the Seiko Prospex Turtle SRPE93 is the addition of a lume pip at the 3 o’clock marker. This was introduced to meet the latest ISO dive watch standards to ensure enhanced visibility in low-light conditions.

However, this adjustment led to the removal of the beveling around the day/date window, which remains intact on the SRP777. If you appreciate the vintage-inspired detail and added depth that the beveling provides, the SRP777 might be the more appealing option.

However, if you prioritize lume and low light legibility, then the SRPE93’s additional Lumibrite pip will no doubt serve you better. 

The Case Back Decoration 

Both watches feature the classic Seiko tsunami wave motif on the case back, a signature design element in the Prospex series. However, the text has been updated in the SRPE93 to reflect modern ISO certification requirements. The SRP777’s case back reads “Air Diver’s 200m,” while the SRPE93 now simply states “Diver’s Watch 200m.”

While this change does not impact performance, some collectors might prefer the original wording as a nod to Seiko’s long-standing dive watch heritage. 

Which One Is Right for You? 

Choosing between the Seiko Prospex Turtle SRP777 and SRPE93 ultimately depends on what you prioritize in a dive watch.

If you appreciate subtle vintage aesthetics and small nostalgic details like the beveled day/date window and original case back text, and prefer a slightly more compact fit, the SRP777 is a fantastic choice.

However, if you’re looking for a more modernized version with updated ISO compliance, superior lume at the 3 o’clock position, and don’t mind the lack of beveling, then the SRPE93 is the way to go.

Conclusion

At the end of the day, choosing between the Seiko Prospex Turtle SRP777 and the SRPE93 comes down to personal preference. If I had to pick, I’d go for the Seiko SRPE93 simply because I believe you can never have too much lume on a dive watch.

The additional lume at the 3 o’clock marker ensures even better visibility in low-light conditions which is a key factor for me. 

That said, I completely understand why many collectors are drawn to the Turtle SRP777. It carries a piece of Seiko’s history with its vintage-inspired design elements, including the beveled day-date window, which adds a nostalgic charm. For those who appreciate subtle nods to classic models, the SRP777 is an appealing option. 

Practicality is another consideration. The SRPE93 is still in production and can be ordered easily, typically retailing for around $495. It offers a lot of watch for an affordable price, making it a solid choice for those who want a brand-new, readily available timepiece.

On the other hand, the SRP777 has been discontinued, meaning you’ll need to explore the second-hand market for this one. While pre-owned models are generally more affordable, averaging around $400, they may be harder to find in good condition. 

Ultimately, these two watches are incredibly similar in both aesthetics and specifications. To the untrained eye, it would take a keen collector to spot the differences when one is on your wrist.

But in the end, what matters most is what you value in a watch, whether it’s modern practicality or vintage charm. No matter which you choose, both are excellent examples of Seiko’s dive watch prowess, proving that the Turtle remains a true icon in the world of horology.