Seiko Sumo vs Turtle: Different Enough To Matter ​

seiko sumo vs turtle

If you buy through links on our site, we may earn an affiliate commission. Details

Seiko Sumo vs Turtle: Different Enough To Matter

SEIKO PROSPEX Men's Watch Diver Mechanical self-winding (with manual winding) Waterproof 200m Hard Rex SBDC033J1

Seiko SBDC033 Sumo (Blumo) Blue Version

Seiko Men's Automatic Analog Watch with Stainless Steel Strap - SRP773K1, Blue/Silver, Bracelet

Seiko SRP773 Turtle

The Seiko Sumo and Turtle models from the Prospex range are both stylish looking dive watches that are very hard to pick between.

Sure, there are some obvious differences in size, style and shape that you can clearly see from the images above. However, in my opinion, the devil is in the detail.

So, in this comparison review I am going to dive deep (got to love a good pun) and see what exactly the difference between the two models are, apart from the catchy names! 

The Differences Between Two

Below is a technical side by side comparison of the Seiko Sumo and Turtle, so you can quickly and easily see the main differences.

SEIKO PROSPEX Men's Watch Diver Mechanical self-winding (with manual winding) Waterproof 200m Hard Rex SBDC033J1
Seiko Men's Automatic Analog Watch with Stainless Steel Strap - SRP773K1, Blue/Silver, Bracelet
Model number
SBDC033
SRP773
Movement
Seiko 6R15 Automatic
Seiko Automatic 4R36
Power reserve
50 hours
41 hours
Complications
Day
Day/Date
Diameter
44mm
45mm
Thickness
13.3mm
13.4mm
Strap Thickness
20mm
22mm
Strap
Stainless steel
Stainless steel
Clasp
Deployant with safety
Deployant with safety
Dial Window
Hardlex
Hardlex
Case
Stainless Steel
Stainless Steel
Bezel
120 click One Way Rotating Elapsed Timing Bezel
120 click One Way Rotating Elapsed Timing Bezel
Water Resistance
200 Meters / 656 Feet / 20 ATM
200 Meters / 656 Feet / 20 ATM
SEIKO PROSPEX Men's Watch Diver Mechanical self-winding (with manual winding) Waterproof 200m Hard Rex SBDC033J1
Model number
SBDC033
Movement
Seiko 6R15 Automatic
Power reserve
50 hours
Complications
Day
Diameter
44mm
Thickness
13.3mm
Strap Thickness
20mm
Strap
Stainless steel
Clasp
Deployant with safety
Dial Window
Hardlex
Case
Stainless Steel
Bezel
120 click One Way Rotating Elapsed Timing Bezel
Water Resistance
200 Meters / 656 Feet / 20 ATM
Seiko Men's Automatic Analog Watch with Stainless Steel Strap - SRP773K1, Blue/Silver, Bracelet
Model number
SRP773
Movement
Seiko Automatic 4R36
Power reserve
41 hours
Complications
Day/Date
Diameter
45mm
Thickness
13.4mm
Strap Thickness
22mm
Strap
Stainless steel
Clasp
Deployant with safety
Dial Window
Hardlex
Case
Stainless Steel
Bezel
120 click One Way Rotating Elapsed Timing Bezel
Water Resistance
200 Meters / 656 Feet / 20 ATM

The Dial/Face

seiko sumo face
Seiko Sumo Face
seiko turtle face
Seiko Turtle Face
Although very similar, these two watches have a few differences worth noting. First, the hands on the Sumo are thicker and more stylish in my opinion. They have a taper as they head towards their point. The Turtle’s hands are pointier, with the minute hand an arrow shape, and the hour hand stubby with a strange point on the end. The second hands are also quite different with the Sumo having one that is in mine with the other hands, and is lumed, while the Turtle has a simple, thing hand with a black tail. Somehow, it does not quite match the rest. The hour markers on both watches are typical dive watch style circles and rhomboids, however it is the split at 12 o’clock and the points on the Turtle’s rhomboids that stand out. The minute train on the outside ring is also far more subtle on the Sumo, which although nicer to look at, is perhaps not as helpful for a dive watch. However, I am sure most of you will never dive with either of them, right? Then there is the clear difference in complications, the Turtle has the addition of the date over the simple day on the Sumo.

The Bezel

Both have a matching blue 120 click dive bezel, however the Sumo’s is significantly thicker with weightier arabic numbers. The Grip on the outside of the bezel itself is more subtle on the Sumo, and obviously more pronounced on the Turtle.

The Case

The Turtle, like it’s brother the Tuna, has a very distinctive shape when it comes to the case. Some love it, others hate it. But it certainly stands out.

It is almost like a full circle, cut off only at the lugs, and it makes for a far wider looking watch which may suit some of you wanting a bigger more modern looking watch. The top of the case is also very flat, compared to the tapering you can see on the sides of the Sumo. However, they both share the same brushed stainless steel material.

The Crown

Seiko’s dive watches often see their crowns at 4 o’clock, so it’s perhaps not surprise both watches have this feature too.

With the extra width on the case, Seiko have also embedded the crown, giving it some extra protection. Although both are screw-down crowns as you would expect from a 200m spec dive watch.

The Sumo has the addition of a Seiko S stamped on the polished crown face and a far more grip-worthy pattern then the Turtle. However, both a quite easy to adjust by all accounts.

And remember, both these watches have self-winding and hacking

!

SEIKO PROSPEX Men's Watch Diver Mechanical self-winding (with manual winding) Waterproof 200m Hard Rex SBDC033J1

The Bracelet

Not a huge amount to report on the bracelets, as they are both fairly standard Seiko all stainless steel.

They have a deployant clasp with safety, which is becoming “run of the mill” for dive watches, but useful nonetheless. They both have micro-adjustments which are again something you would expect to help fit the watch well to your wrist.

The biggest difference between the two is the 20 vs 22mm strap width, with the Turtle being wider. This also suits the wider looking case, so a great choice if you ask me.

SEIKO PROSPEX Men's Watch Diver Mechanical self-winding (with manual winding) Waterproof 200m Hard Rex SBDC033J1

The Movement

The Sumo and the Turtle both have automatic movements with self-winding and hacking. And their resulting case thickness is also almost exactly the same.

So, it begs the question, is there anything worth mentioning here?

Well, the Sumo has Seiko’s 6R15 with 50 hours of power reserve, while the Turtle has the 4R36 with only 41 hours. So you can safely wait 2 days (or 48 hours) before having to charge the Sumo.

And, according to some of the Seiko fans, the 6R15 has some better parts in it which leads to great accuracy. Which overall, also saves you from adjusting it more often. Something you have to live with when you buy an automatic anyway.

Which Should You Choose

These two watches are so similar that it’s almost impossible to choose. I would honestly buy both, if I could.

The main differences if you ask me are in the shape of the case/dial and the movement (including day vs day/date option).

So, it’s either a matter of taste or a preference for the specifics of the movement.

In terms of color, I have only compared the two blue ones here, but there is also a black Sumo (image below) and various Turtles available.

Seiko Prospex SBDC031 Mens Wristwatch Diving Watch

New Seiko SRP777 Prospex Automatic Black Rubber Strap Diver's Men's Watch

Recent articles