Complete guide to the Seiko Turtle

Seiko Turtle
Photo by Seiko

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.

Turtle 6306

Ref: YCS018 (6306-7000, 6306-7001)
Caliber: 6306
Year: 1976

45mm stainless steel case, Hardlex crystal, screw-down crown, 21 jewels, 21,600 bph, hacking function.

Turtle 6306 SCUBAPRO 450

Ref: ? (6306-7001)
Caliber: 6306
Year: 1978

45mm stainless steel case, Hardlex crystal, screw-down crown, 21 jewels, 21,600 bph, hacking function.

ATTENTION: a substantial part of the specimens that appear on the market are regular 6306-7001 with reprinted dial.

Turtle 6306 MSST1978-79

Ref: ? (6306-7001)
Calibro: 6306

45mm stainless steel case, Hardlex crystal, screw-down crown, 21 jewels, 21,600 bph, hacking function.

Turtle 6306 MSST1979-80

Ref: ? (6306-7001)
Calibro: 6306

45mm stainless steel case, Hardlex crystal, screw-down crown, 21 jewels, 21,600 bph, hacking function.

Turtle 6309

Ref: DE095 (6309-7040, 6309-7049)
Caliber: 6309
Year: 1976

45mm stainless steel case, Hardlex crystal, screw-down crown, 17 jewels, 21,600 bph.

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.

Turtle 773

Ref: SRP773 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle 775

Ref: SRP775 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle 777

Ref: SRP777 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle 779

Ref: SRP779 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Batman

Ref: SRP787 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Coke

Ref: SRP789 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Zimbe Grey Turtle

Ref: SRPA19 (4R36-05D0)
Caliber: 4R36
Limited Edition of 1299 pieces.

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle PADI

Ref: SRPA21 (4R36-05H0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Green Turtle

Ref: SRPB01 (4R36-?)
Caliber: 4R36
Limited Edition of 3500 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Blue Lagoon Turtle

Ref: SRPB11 (4R36-06A0)
Caliber: 4R36
Limited Edition of 6000 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Golden Turtle

Ref: SRPC44 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Ninja Turtle

Ref: SRPC49 (4R36-06L0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Gray Sunburst

Ref: SRPC23 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Deep Blue Turtle

Ref: SRPC25 (4R36-04Y0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Black Gold Turtle

Ref: SRPC48 (4R36-?)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Save The Ocean v1

Ref: SRPC91 (4R36-05H0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Nemo

Ref: SRPC95 (4R36-06T0)
Caliber: 4R36
Limited Edition of 500 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Grey Dawn

Ref: SRPD01 (4R36-06Y0)
Caliber: 4R36
Limited Edition of 2018 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Save The Ocean v2

Ref: SRPD11 (4R36-05H0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle STO Great White Shark

Ref: SRPD21 (4R36-07D0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Caribbean Turtle

Ref: SRPD43 (4R36-07F0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Sea Grapes Okinawa

Ref: SRPD45 (4R36-07K0)
Caliber: 4R36
Limited Edition of 1800 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Darth Turtle

Ref: SBDY041 (4R36-07M0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Green Hole

Ref: SRPD48 (4R36-?)
Caliber: 4R36
Limited Edition of 500 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Turtle Green Hulk

Ref: SBDY039 (4R36-07M0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Black Gold Turtle

Ref: SRPD46 (4R36-07L0)
Caliber: 4R36

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Aussie Turtle

Ref: SRPD50 (4R36-07J0)
Caliber: 4R36
Limited Edition of 1000 pieces.

45mm stainless steel case, Hardlex crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

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.

King Turtle Black Waffle

Ref: SRPE03 (4R36-06Z0)
Caliber: 4R36

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

King Turtle Green Waffle

Ref: SRPE05 (4R36-06Z0)
Caliber: 4R36

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

King Turtle Save The Ocean

Ref: SRPE07 (4R36-06Z0)
Caliber: 4R36

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

King Turtle Manta Ray 2020

Ref: SRPE39 (4R36-06Z0)
Caliber: 4R36

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

King Turtle Manta Ray 2021

Ref: SRPF77 (4R36-06Z0)
Caliber: 4R36

45mm stainless steel case, sapphire crystal, screw-down crown, 24 jewels, 41 hours power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle

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

Black Mini Turtle

Ref: SRPC35 (4R35-01Y0)
Caliber: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Black Mini Turtle

Ref: SRPC37 (4R35-01Y0)
Caliber: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Blue Mini Turtle

Ref: SRPC39 (4R35-01Y0)
Caliber: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle PADI

Ref: SRPC41 (4R35-02K0)
Caliber: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle Zimbe Green

Ref: SRPD17 (4R35-03H0)
Caliber: 4R35
Limited Edition of 999 pieces.

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle Zimbe Yellow

Ref: SRPD19 (4R35-03K0)
Caliber: 4R35
Limited Edition of 999 pieces.

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Green Mini Turtle

Ref: SBDY083 (4R35-04H0)
Calibro: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle

Ref: SBDY085 (4R35-?)
Calibro: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Mini Turtle

Ref: SBDY087 (4R35-?)
Calibro: 4R35

42mm stainless steel case, Hardlex crystal, screw-down crown, 23 jewels, 41 hour power reserve, 21,600 bph, manual winding, hacking function.

Summary of the models

Original Turtle

NicknameRef.Other Ref.MC Ref.CaliberLimited
Turtle 6306YCS0186306-7000
6306-7001
6306No
Turtle 6306 SCUBAPRO 450?6306-70016306No
Turtle 6306 MSST1978-79?6306-70016306No
Turtle 6306 MSST1979-80?6306-70016306No
Turtle 6309DE0956309-7040
6309-7049
6309No

New generation of Turtle

NicknameRef.Other Ref.MC Ref.CaliberLimited
Turtle 773SRP773SRPE89, SRP773J1, SRP773J, SRP773K1, SRP773K4R36-04Y04R36No
Turtle 775SRP775SRPE91, SRP775J1, SRP775J, SRP775K1, SRP775K4R36-04Y04R36No
Turtle 777SRP777SRPE93, SBDY015, SRP777J1, SRP777J, SRP777K1, SRP777K4R36-04Y04R36No
Turtle 779SRP779SRPE95, SRP779J1, SRP779J, SRP779K1, SRP779K4R36-04Y04R36No
Turtle BatmanSRP787SRP787K1, SRP787K4R36-04Y04R36No
Turtle CokeSRP789SRP789K1, SRP789K4R36-04Y04R36No
Turtle CostcoSRPA854R36-04Y04R36No
Grey Zimbe TurtleSRPA19SRPA19K1, SRPA19K4R36-05D04R36Yes (1299)
Turtle PADISRPA21SRPE99, SBDY017, SRPA21J1, SRPA21J, SRPA21K1, SRPA21K, SRPE99K1, SRPE99K4R36-05H04R36No
Green TurtleSRPB01SRPB01K1, SRPB01K?4R36Yes (3500)
Blue Lagoon TurtleSRPB11SRPB11J1, SRPB11J, SRPB11K1, SRPB11K4R36-06A04R36Yes (6000)
Golden TurtleSRPC44SRPC44J1, SRPC44J, SRPC44K1, SRPC44K4R36-04Y04R36No
Ninja TurtleSRPC49SBDY005, SRPC49J1, SRPC49J, SRPC49K1, SRPC49K4R36-06L04R36No
Turtle Gray SunburstSRPC23SRPF13, SRPC23J1, SRPC23J, SRPC23K1, SRPC23K4R36-04Y04R36No
Deep Blue TurtleSRPC25SRPF15, SBDY013, SRPC25J1, SRPC25J, SRPC25K1, SRPC25K4R36-04Y04R36No
Black Gold TurtleSRPC48SBDY004, SRPC48J1, SRPC48J?4R36No
Turtle Save The Ocean v1SRPC91SBDY021, SRPC91J1, SRPC91J, SRPC91K1, SRPC91K4R36-05H04R36No
Turtle NemoSRPC95SBDY023, SRPC95J1, SRPC95J, SRPC95K1, SRPC95K4R36-06T04R36Yes (500)
Turtle Grey DawnSRPD01SRPD01K1, SRPD01K4R36-06Y04R36Yes (2018)
Turtle Save The Ocean v2SRPD11SBDY027, SRPD11J1, SRPD11J, SRPD11K1, SRPD11K4R36-05H04R36No
Turtle STO Great White SharkSRPD21SBDY031, SRPD21J1, SRPD21J, SRPD21K1, SRPD21K4R36-07D04R36No
Caribbean TurtleSRPD434R36-07F04R36No
Turtle Sea Grapes OkinawaSRPD45SRPD45K1, SRPD45K4R36-07K04R36Yes (1800)
Darth TurtleSBDY041SBDY041J1, SBDY041J4R36-07M04R36No
Turtle Green HoleSRPD48SRPD48J1, SRPD48J?4R36Yes (500)
Turtle Green HulkSBDY039SBDY039J1, SBDY039J4R36-07M04R36No
Black Gold TurtleSRPD46SRPD46J1, SRPD46J, SRPD46K1, SRPD46K4R36-07L04R36No
Aussie TurtleSRPD50SRPD50K1, SRPD50K4R36-07J04R36Yes (1000)

King Turtle

NicknameRef.Other Ref.MC Ref.CaliberLimited
King Turtle Black WaffleSRPE03SBDY049, SRPE03J1, SRPE03J, SRPE03K1, SRPE03K4R36-06Z04R36No
King Turtle Green WaffleSRPE05SBDY051, SRPE05J1, SRPE05J, SRPE05K1, SRPE05K4R36-06Z04R36No
King Turtle Save The OceanSRPE07SBDY047, SRPE07J1, SRPE07J, SRPE07K1, SRPE07K4R36-06Z04R36No
King Turtle Manta Ray 2020SRPE39SBDY063, SRPE39J1, SRPE39J, SRPE39K1, SRPE39K4R36-06Z04R36No
King Turtle Manta Ray 2021SRPF77SBDY079, SRPF77J1, SRPF77J, SRPF77K1, SRPF77K4R36-06Z04R36No

Mini Turtle

NicknameRef.Other Ref.MC Ref.CaliberLimited
Black Mini TurtleSRPC35SRPC35J1, SRPC35J, SRPC35K1, SRPC35K4R35-01Y04R35No
Black Mini TurtleSRPC37SRPC37J1, SRPC37J, SRPC37K1, SRPC37K4R35-01Y04R35No
Blue Mini TurtleSRPC39SRPC39J1, SRPC39J, SRPC39K1, SRPC39K4R35-01Y04R35No
Mini Turtle PADISRPC41SRPC41J1, SRPC41J, SRPC41K1, SRPC41K4R35-02K04R35No
Mini Turtle Zimbe GreenSRPD17SRPD17K1, SRPD17K4R35-03H04R35Yes (999)
Mini Turtle Zimbe YellowSRPD19SRPD19K1, SRPD19K4R35-03K04R35Yes (999)
Green Mini TurtleSBDY0834R35-04H04R35No
Mini TurtleSBDY085?4R35No
Mini TurtleSBDY087?4R35No

Movements

SeriesMovements
Original Turtle6306, 6309
New Generation of Turtle4R36
King Turtle4R36
Mini Turtle4R35

Caliber 6306

TypeAutomatic
Power reserve?
Bph21,600
Jewels21
Lift Angle54.5°
Manual windNo
HackingYes

Caliber 6309

TypeAutomatic
Power reserve?
Bph21,600
Jewels17
Lift Angle54.5°
Manual windNo
HackingNo

Caliber 4R36

TypeAutomatic
Power reserve41 hours
Bph21,600
Jewels24
Lift Angle53°
Manual windYes
HackingYes

Caliber 4R35

Technical sheet

TypeAutomatic
Power reserve41 hours
Bph21.600
Jewels23
Lift Angle53°
Manual windYes
HackingYes