Complete guide to the Seiko Turtle

The diver’s watch we know today as the “Turtle” was first introduced by Seiko between 1976 and 1977, and continued to be produced until the late 1980s.

Nearly three decades after the first models left the scene, in 2016 Seiko announced the reintroduction of the much loved turtle shell case diver as part of the Prospex line.

Greeted with great enthusiasm by fans, the new Seiko Turtle immediately became a best seller among the entry-level divers, and with the increasing number of new editions have also caught the attention of many collectors.

Original Turtle

The Turtle 6306 appears in the official Seiko catalog of 1977 under the reference YCS018. It seems that the first examples, intended for the Japanese domestic market, had the reference case movement 6306-7000, which later becomes 6306-7001 (any differences between them are not known).

With the reference 6306-7001 we also find the rare SCUBAPRO 450, highly sought after by collectors. The only difference between a regular 6306-7001 and the SCUBAPRO 450 is the print on the dial. These watches were the result of a collaboration between Seiko and Scubapro, a manufacturer of diving equipment.

Again with the same reference 6306-7001 there are also the Turtle MSST1978-79 and MSST1979-80, made for the McMurdo Sound Sediment and Tectonic Study expeditions to Antarctica. As with the Scubapro, the only difference in the watch is the print on the dial.

The Turtle 6309 housed a caliber with 17 jewels, less than the 21 of the 6306, and no hacking function. This model was mainly intended for the international market, and is found with the case-movement references 6309-7040 and 6309-7049, the latter dedicated to North America.

New generation of Turtle

In a December 2015 press release, Seiko announces the reintroduction of the Turtle, as part of the Prospex watch line, in four different colors: 773 (blue), 775 (black/gold), 777 (black), 779 (pepsi).

Over the following years, other references were introduced, all based on the 4R36 automatic movement, with hacking and manual winding functions.

King Turtle

The references nicknamed “King Turtle” introduce some upgrades, such as sapphire crystal and ceramic inserts. The size of the case remains the same as the classic Turtle.

Mini Turtle

As the name “Mini Turtle” suggests, this series is a reinterpretation of the original Turtle, but with a smaller size.

Summary of the models

Original Turtle

Nickname	Ref.	Other Ref.	MC Ref.	Caliber	Limited
Turtle 6306	YCS018	–	6306-7000 6306-7001	6306	No
Turtle 6306 SCUBAPRO 450	?	–	6306-7001	6306	No
Turtle 6306 MSST1978-79	?	–	6306-7001	6306	No
Turtle 6306 MSST1979-80	?	–	6306-7001	6306	No
Turtle 6309	DE095	–	6309-7040 6309-7049	6309	No

New generation of Turtle

Nickname	Ref.	Other Ref.	MC Ref.	Caliber	Limited
Turtle 773	SRP773	SRPE89, SRP773J1, SRP773J, SRP773K1, SRP773K	4R36-04Y0	4R36	No
Turtle 775	SRP775	SRPE91, SRP775J1, SRP775J, SRP775K1, SRP775K	4R36-04Y0	4R36	No
Turtle 777	SRP777	SRPE93, SBDY015, SRP777J1, SRP777J, SRP777K1, SRP777K	4R36-04Y0	4R36	No
Turtle 779	SRP779	SRPE95, SRP779J1, SRP779J, SRP779K1, SRP779K	4R36-04Y0	4R36	No
Turtle Batman	SRP787	SRP787K1, SRP787K	4R36-04Y0	4R36	No
Turtle Coke	SRP789	SRP789K1, SRP789K	4R36-04Y0	4R36	No
Turtle Costco	SRPA85	–	4R36-04Y0	4R36	No
Grey Zimbe Turtle	SRPA19	SRPA19K1, SRPA19K	4R36-05D0	4R36	Yes (1299)
Turtle PADI	SRPA21	SRPE99, SBDY017, SRPA21J1, SRPA21J, SRPA21K1, SRPA21K, SRPE99K1, SRPE99K	4R36-05H0	4R36	No
Green Turtle	SRPB01	SRPB01K1, SRPB01K	?	4R36	Yes (3500)
Blue Lagoon Turtle	SRPB11	SRPB11J1, SRPB11J, SRPB11K1, SRPB11K	4R36-06A0	4R36	Yes (6000)
Golden Turtle	SRPC44	SRPC44J1, SRPC44J, SRPC44K1, SRPC44K	4R36-04Y0	4R36	No
Ninja Turtle	SRPC49	SBDY005, SRPC49J1, SRPC49J, SRPC49K1, SRPC49K	4R36-06L0	4R36	No
Turtle Gray Sunburst	SRPC23	SRPF13, SRPC23J1, SRPC23J, SRPC23K1, SRPC23K	4R36-04Y0	4R36	No
Deep Blue Turtle	SRPC25	SRPF15, SBDY013, SRPC25J1, SRPC25J, SRPC25K1, SRPC25K	4R36-04Y0	4R36	No
Black Gold Turtle	SRPC48	SBDY004, SRPC48J1, SRPC48J	?	4R36	No
Turtle Save The Ocean v1	SRPC91	SBDY021, SRPC91J1, SRPC91J, SRPC91K1, SRPC91K	4R36-05H0	4R36	No
Turtle Nemo	SRPC95	SBDY023, SRPC95J1, SRPC95J, SRPC95K1, SRPC95K	4R36-06T0	4R36	Yes (500)
Turtle Grey Dawn	SRPD01	SRPD01K1, SRPD01K	4R36-06Y0	4R36	Yes (2018)
Turtle Save The Ocean v2	SRPD11	SBDY027, SRPD11J1, SRPD11J, SRPD11K1, SRPD11K	4R36-05H0	4R36	No
Turtle STO Great White Shark	SRPD21	SBDY031, SRPD21J1, SRPD21J, SRPD21K1, SRPD21K	4R36-07D0	4R36	No
Caribbean Turtle	SRPD43	–	4R36-07F0	4R36	No
Turtle Sea Grapes Okinawa	SRPD45	SRPD45K1, SRPD45K	4R36-07K0	4R36	Yes (1800)
Darth Turtle	SBDY041	SBDY041J1, SBDY041J	4R36-07M0	4R36	No
Turtle Green Hole	SRPD48	SRPD48J1, SRPD48J	?	4R36	Yes (500)
Turtle Green Hulk	SBDY039	SBDY039J1, SBDY039J	4R36-07M0	4R36	No
Black Gold Turtle	SRPD46	SRPD46J1, SRPD46J, SRPD46K1, SRPD46K	4R36-07L0	4R36	No
Aussie Turtle	SRPD50	SRPD50K1, SRPD50K	4R36-07J0	4R36	Yes (1000)

King Turtle

Nickname	Ref.	Other Ref.	MC Ref.	Caliber	Limited
King Turtle Black Waffle	SRPE03	SBDY049, SRPE03J1, SRPE03J, SRPE03K1, SRPE03K	4R36-06Z0	4R36	No
King Turtle Green Waffle	SRPE05	SBDY051, SRPE05J1, SRPE05J, SRPE05K1, SRPE05K	4R36-06Z0	4R36	No
King Turtle Save The Ocean	SRPE07	SBDY047, SRPE07J1, SRPE07J, SRPE07K1, SRPE07K	4R36-06Z0	4R36	No
King Turtle Manta Ray 2020	SRPE39	SBDY063, SRPE39J1, SRPE39J, SRPE39K1, SRPE39K	4R36-06Z0	4R36	No
King Turtle Manta Ray 2021	SRPF77	SBDY079, SRPF77J1, SRPF77J, SRPF77K1, SRPF77K	4R36-06Z0	4R36	No

Mini Turtle

Nickname	Ref.	Other Ref.	MC Ref.	Caliber	Limited
Black Mini Turtle	SRPC35	SRPC35J1, SRPC35J, SRPC35K1, SRPC35K	4R35-01Y0	4R35	No
Black Mini Turtle	SRPC37	SRPC37J1, SRPC37J, SRPC37K1, SRPC37K	4R35-01Y0	4R35	No
Blue Mini Turtle	SRPC39	SRPC39J1, SRPC39J, SRPC39K1, SRPC39K	4R35-01Y0	4R35	No
Mini Turtle PADI	SRPC41	SRPC41J1, SRPC41J, SRPC41K1, SRPC41K	4R35-02K0	4R35	No
Mini Turtle Zimbe Green	SRPD17	SRPD17K1, SRPD17K	4R35-03H0	4R35	Yes (999)
Mini Turtle Zimbe Yellow	SRPD19	SRPD19K1, SRPD19K	4R35-03K0	4R35	Yes (999)
Green Mini Turtle	SBDY083	–	4R35-04H0	4R35	No
Mini Turtle	SBDY085	–	?	4R35	No
Mini Turtle	SBDY087	–	?	4R35	No

Movements

Series	Movements
Original Turtle	6306, 6309
New Generation of Turtle	4R36
King Turtle	4R36
Mini Turtle	4R35

Caliber 6306

Type	Automatic
Power reserve	?
Bph	21,600
Jewels	21
Lift Angle	54.5°
Manual wind	No
Hacking	Yes

Caliber 6309

Type	Automatic
Power reserve	?
Bph	21,600
Jewels	17
Lift Angle	54.5°
Manual wind	No
Hacking	No

Caliber 4R36

Type	Automatic
Power reserve	41 hours
Bph	21,600
Jewels	24
Lift Angle	53°
Manual wind	Yes
Hacking	Yes

Caliber 4R35

Technical sheet

Type	Automatic
Power reserve	41 hours
Bph	21.600
Jewels	23
Lift Angle	53°
Manual wind	Yes
Hacking	Yes