Seiko 5 Sports SRPD51K1 review

What it is

This is the blue member of the SRPD family of Seiko 5 Sports watches, which share the same case and movement and differ mainly in dial and bezel colour. It sits at the entry point for Seiko automatics, below the Prospex range, and is one of the most popular first automatics in the UK because of its looks and straightforward build.

The Seiko 5 name goes back to 1963 and the idea of five practical features: automatic winding, a day-date display, water resistance, a recessed crown and a durable case and bracelet. The modern line keeps that practical spirit.

The movement

The watch runs on Seiko's in-house 4R36 automatic. It has a power reserve of about 41 hours, and can be hand-wound and has a seconds-stop for precise setting. Seiko's published accuracy range is wide, so expect gains or losses of a few seconds a day on average, with some variation between examples. A regulation by a watchmaker can tighten it. Plan on a service every several years, and a caseback window shows the movement.

A seconds-stop and hand-winding make setting the time easier than on older Seiko 5 models, which could not do either.

On the wrist

It is a 42.5 mm case on a 22 mm steel bracelet, so it reads as a medium-large sports watch. The date and day display sits at 3. The bracelet is robust and uses a simple clasp; it is functional rather than fine. The blue sunray finish changes with the light and goes with most casual clothes. On smaller wrists the lugs may overhang, so look at the lug-to-lug figure on the listing.

Water and everyday wear

It is rated to 100 m, which means swimming and snorkelling are fine, but it is not an ISO diver and is not intended for scuba. The crystal is Hardlex, Seiko's tough mineral glass, which resists impacts but will scratch more easily than sapphire. The hands and markers carry lume. Avoid pulling the crown out while wet.

The rotating bezel is handy for timing short intervals, but with only a 100 m rating this is not a proper dive tool, so treat the bezel as a styling and convenience feature.

Against the alternatives

The Seiko 5 Sports SRPD55K1 is the black version and the Seiko 5 Sports SRPD63K1 the green. The Orient Kamasu RA-AA0002L19B has a sapphire crystal and 200 m rating in a similar blue. If you want a Swiss automatic with a longer reserve, the Tissot PRX Powermatic 80 T137.407.11.041.00 is a more refined alternative.

Who it's for, and who should skip it

It is for anyone wanting an affordable, readable, hard-wearing first automatic with some character. Skip it if you want sapphire glass, accuracy to the second, or a slim case. A quartz or solar watch will keep better time with less upkeep.