At this point, I've reviewed a lot of Seiko divers, including a bunch of the now-iconic Turtle. Seiko also makes a number of cool field watches with compass bezels and other useful features. Thus, I was happy to get this Prospex SRPJ31, which came my way via Random Rob. It's nicknamed the Tortoise, likely due to its similarity to the Turtle, and its olive coloring.

Seiko Tortoise Land SRPJ31 First Impressions
Two things surprised me when I first took the Tortoise out of its box. First, the dial texture looks much more pronounced than expected. This, combined with the tight gaps between the dial, hands, and crystal, gives it a cool look, even when viewed from the side (reminding me a bit of the off-angle legibility of the Tudor Pelagos and Sinn U1 and U50).


The other surprise was the dimensions. I had assumed this model was a Turtle with a different bezel, but, like the other Compass Seiko I reviewed, the Field Monster, the Tortoise has a different case. But unlike the Monster, the Tortoise is smaller than the Turtle, not bigger.
Seiko Tortoise Land SRPJ31 Details
Although it's resized, the case design and finishing are carried over from other Seiko Turtles. A brushed top surface meets polished sides. In this case, it is coated in black. The bezel is half olive and half black, with compass markings.

The textured dial is dark gray, with an applied logo and white and red printing. The applied hour markers are metal with sharp edges.

The date aperture sits at 4:30, slightly offset from the unsigned crown at 4. This model also features an upgrade to a sapphire crystal.

Wearing the Seiko Tortoise Land SRPJ31
The smaller 42mm case width (and 45mm height) makes the Tortoise more wearable than its larger dive-watch brother. Although I never minded the turtle's size, this feels more appropriate for a field-style watch. It's still a substantial watch, but Seiko's tight lugs and the smaller bezel make it look compact.

It's also thinner than the Turtle (12mm) despite offering the same 200m of water resistance.


Navigating with a watch like this involves orienting the hour hand in relation to the sun and rotating the compass bezel. I love a bezel with crisp clicks, but the friction setup used makes sense in this application. A coin edge treatment makes it easy to grip.

The distinctive red arrow-shaped hour hand is designed to aid in this. It also improves general legibility, as it's easy to distinguish from the minute hands.

Seiko's Lumibrite makes it easy to read at night as well.

Original strap and replacement straps for the Seiko Tortoise Land SRPJ31
Unlike the Turtle, the Tortoise uses 20mm straps. It comes with an olive green canvas strap with a thicker weave than our Sailcloth straps.


It looks awesome on the new Olive Sketchy Boyz Watch Club Divecore straps, but red, orange, or black straps would look great on it too!

Here is a list of straps that would look great with this watch. At the end of the article, you'll also find photos of some of our favorite combinations. You can also view our Guide to Choosing a Watch Strap.
-Deployant Rubber
-Ridge Rubber
-Tropical Rubber
-Premium Sailcloth
-Smooth Rubber
-Rubber and Sailcloth Hybrid Straps
-Pro Diver
-Vented Rubber
-Slim Ridge Rubber
-Waffle Rubber
-Beads of Rice Bracelets
-Elastic
Seiko Tortoise Land SRPJ31 Movement
The Tortoise uses the Seiko 4R35, which is the brand's workhorse automatic movement with only a Date. It offers a 41-hour power reserve, wound by Seiko's Magic Lever automatic winding system. It operates at 21,600 vibrations per hour on 24 jewels. The caseback, which sits behind, features ground-to-air emergency signal codes.

Seiko Tortoise Land SRPJ31 Conclusion
If you are a Seiko fan but don't need a diver or just want something smaller than the Turtle, the Land Tortoise is a great alternative. Some might find the compass bezel more useful, and this one features some attractive styling upgrades, plus a sapphire crystal.
Seiko Tortoise Land SRPJ31 Specifications
Name: Seiko Prospex Land US Special Edition
Reference Number: SRPJ31
Price: $595
Diameter: 42.4mm
Height: 45mm
Thickness: 12mm
Lug Width: 20mm
Weight: 88g
Movement: Caliber 4R35
Power Reserve: 41 hours
Water Resistance: 200m
Crystal: Sapphire
Crown: Screw-down
Bezel: Friction
Strap/Bracelet: Canvas
Shop Other Straps for the Seiko Tortoise Land SRPJ31
Divecore


Deployant Sailcloth


Deployant FKM Rubber


Hook and Loop Elastic

