The history of Seiko Dive Watches goes back to 1965 with their very first model. From then on Seiko have lead the way in innovation, design technology, materials and style. You may have already looked at the Seiko Tuna and Samurai – here we look at the Seiko Turtle dive watch.


An introduction

In 1976 Seiko released the first of their “cushion cased” or “turtle shell” style diver’s watches. The Seiko 6306 & 6309 were produced from 1976 (1) until 1988. Recognisable from their soft cushion shaped case these watches also featured a recessed crown at the 4 o’clock position and day / date indicators. Both models were driven by an automatic (mechanical self wind) movement.

Seiko SRP777K1 – automatic 200m divers watch

>> Back to Top

LIVE feed sales

UK sellers – updated 17th September 2019

Seiko Turtle - LIVE feed - UK sellers

>> Back to Top

Available online now is an affiliated partner of Here’s a selection from their range of Seiko 200m dive watches (not specifically the “Turtle” case style)

LIVE feed sales

USA Sellers – updated September 17, 2019

Seiko Turtle - LIVE feed - USA sellers

>> Back to Top

Specification (current models)

The Seiko Turtle was re-introduced in 2016. Available in 4 variants

  • steel with black dial / bezel (SRP777)
  • steel with black / gilt detailing (SRP775)
  • steel with blue detailing (SRP773)
  • steel with “pepsi” red & blue detailing (SRP779)

Since then Seiko have added a couple of new variants

  • steel with PADI red & blue details (SRPA21K1)
  • all black tactical version (SRPC49K1)
Seiko SRPC49K1 – the Tactical Turtle in all black


Case Material : Stainless steel

Glass Material : Hardlex

Band Material : Silicon

Case Thickness : 13.4㎜
Case Diameter : 45㎜


Calibre Number : 4R36

Movement Type : Automatic with manual winding capacity

Duration : Approx. 41 hours

Accuracy : +45 to -35 seconds per day

Other Details

LumiBrite : Lumibrite on hands and indexs

Water Resistance : 200m / 660ft diver’s


  • 24 jewels
  • Day/Date display
  • Screw case back
  • Stop seconds hand function
  • Unidirectional rotating bezel

>> Back to Top

Old Turtle versus New Turtle

The main differences between the new Seiko Turtle watches and those from 1978 to 1988 (6306 / 6309) are as follows (2)

  • Case depth increased from 13mm to 14mm
  • Addition of a softer silicone strap (previously harder rubber)
  • The lollipop on the seconds hand was moved from head to tail
  • Seiko 6309 – 17 jewel automatic movement – non-winding non-hacking changed to Calibre 4R36 with 24 jewels with hand wind and seconds stop function.

>> Back to Top

Video Reviews

Seiko Turtle PADI SRPA21K1 Prospex Review

YouTube video

John Egerton’s thoughts on the popular PADI Turtle re-issue from Seiko. Is it worth it?

Seiko Prospex SRPA21 “PADI Turtle” One Week On the Wrist

YouTube video

Ankit Blanket’s review of the Seiko SRPA21 “PADI Turtle” dive watch after one week …

>> Back to Top

External references / further reading

>> Back to Top

If you found this page via a search engine – please pop over to our generic Seiko Divers watch page. You will find plenty more information on iconic styles from Japan’s leading manufacturer of quality dive watches.