Seiko Prospex ‘Astrolabe’ SLA065J1 Limited Edition Watch Review

Joining the Japanese watchmaker’s Save the Ocean series, the new Seiko Prospex ‘Astrolabe’ SLA065J1 watch looks much like others, upholding its modern interpretation exterior of Japan’s first-ever dive watch, the Seiko 62MAS. However, the limited edition of 1,300 pieces stands out rather significantly for its complex engraved dial inspired by the astrolabe, a historical piece of equipment used by sailors to navigate across the sea.

Back in 2018, Seiko introduced a new line of Prospex diving watches called “Save the Ocean”. The series was designed to raise funds and support various marine conservation activities in order to preserve and protect the ocean for future generations. One of these organisations is the Ocean Learning Centre of Fabien Cousteau, grandson of the famous underwater explorer Jacques-Yves Cousteau. Each year since its inaugural debut, Seiko has launched new Save the Ocean watches inspired by different aspects of the ocean, the animals that populate it and in today’s instance, different devices that are used to explore it. Several of the designs launched within the line-up are that of the Seiko Prospex 1965 Modern Re-interpretation watch which celebrates Japan’s first ever dive watch, the Seiko 62MAS. As its name suggests, these watches are not exact replicas of the original diving instrument, but modern reinterpretations, something that also applies to the new Seiko Prospex ‘Astrolabe’ SLA065J1 Limited Edition watch.

The real novelty of the new Seiko Prospex ‘Astrolabe’ SLA065J1 watch is its dial which for the first time see’s the Prospex 1965 Modern Re-interpretation model uniquely engraved with a complex pattern inspired by the astrolabe. An astrolabe is a piece of historical equipment once used by sailors to navigate their way across the seas. It worked by taking measurements from the sun and stars and in turn allowed for global exploration and trade. The mesmerising criss-cross globe-like pattern is applied over a sunray-brushed deep blue backdrop which pairs beautifully with the blue insert on the bezel and the grooved blue rubber strap. The dial of the Seiko Prospex ‘Astrolabe’ watch maintains its diving legacy with large, luminous hour markers and matching luminous hands for the hours, minutes and seconds.

As previously mentioned, the overall aesthetic of the new Seiko Prospex ‘Astrolabe’ SLA065J1 Limited Edition takes inspiration from the brand’s historic 62MAS model but adds a few modernised tweaks here and there. One of these is the case size which sits at 13.1mm tall and 41.3mm in diameter, making room for the broad, scratch-proof blue insert on top of the unidirectional rotating bezel. The bezel is joined by a white 60 minute divers scale and a luminous dot at 12 o’clock. The case here is engineered from classic stainless steel with a super-hard coating and a combination of brushed surfaces and Zaratsu polished bevels. The Seiko Prospex ‘Astrolabe’ SLA065J1 also warrants dual-curved sapphire crystal glass with anti-reflective coating and a screw in crown for a water resistance of 200 metres.

Within its stainless steel architecture, the Seiko Prospex ‘Astrolabe’ SLA065J1 Limited Edition watch hides the automatic winding Calibre 8L35 movement. The movement was developed with diving in mind and so impresses with an accuracy of -10/+15 seconds per day, a power reserve of 50 hours and a 4Hz frequency. It also runs classic central hands for hours, minutes and seconds and provides a date complication at 3 o’clock. Completing the Seiko Prospex ‘Astrolabe’ SLA065J1 watch is a horizontally grooved blue silicon strap secured by a stainless steel pin buckle.

If you’d like to learn more about the new Seiko Prospex ‘Astrolabe’ SLA065J1 watch and get your hands on one of the 1,300 limited edition pieces for yourself, head over to the Jura Watches website here. Alternatively, get in touch with the team by calling 01335 453453 or send us a message at help@jurawatches.co.uk.


  • Case Size: 41.3mm x 13.1mm
  • Case Material: Stainless steel with super-hard coating
  • Bezel: Unidirectional with blue insert and 60 minute diving scale
  • Glass: Dual-curved sapphire crystal with anti-reflective coating
  • Crown: Screw in
  • Case Back: Screwed down
  • Water Resistance: 200 metres
  • Movement: Calibre 8L35 automatic winding
  • Functions: Hours, minutes, seconds, date
  • Power Reserve: 50 hours
  • Jewels: 26
  • Frequency: 28,800vph
  • Accuracy: -10/+15 seconds per day
  • Dial: Blue with astrolabe pattern, Lumibrite hour markers and hands
  • Strap: Blue grooved silicon
  • Buckle: Pin, stainless steel
  • RRP: £2,540
  • Limited Edition: 1,300 pieces
  • Reference: SLA065