Seiko 5 Sports SRPD55

The Seiko 5 Sports SRPD55 is a stainless-steel automatic watch in Seiko's 5 Sports collection, built on the SKX007-inspired case that replaced the discontinued SKX line when the 5 Sports collection launched in 2019. It pairs a black dial and black unidirectional rotating bezel with a 22mm stainless steel bracelet, and runs on Seiko's in-house 4R36 automatic caliber with hacking and hand-winding, a feature the outgoing 7S26-powered SKX lacked. Rated to 100 meters, it trades the SKX's screw-down crown and 200m ISO diver rating for broader design variety and a more modern movement at a similar price point.

The Seiko 5 Sports collection, which the SRPD55 belongs to, launched in 2019 as the direct successor to the SKX line after Seiko discontinued the SKX007 and its siblings. Seiko introduced the new collection in one wave of 27 references, organized into five design-led subcategories the brand calls Sports, Suits, Specialist, Street, and Sense, according to Rescapement's review of the launch. The SRPD55 sits in the "Sports" grouping, which most closely echoes the SKX's original black-dial, black-bezel diver look.

Rescapement traces the lineage further back to the original Seiko 5, launched in 1963 around five defining attributes: automatic winding, a day/date display, water resistance, a recessed crown, and a durable case — criteria the modern 5 Sports line, including the SRPD55, still has to meet. Bespoke Unit's guide to the collection notes that Seiko designed the SRPD range to inherit the SKX's case silhouette and comparable price point while addressing the aftermarket-modding culture that had grown up around the SKX, offering "an ever-growing palette of color combinations" from the outset.

The changeover was not without compromises. Worn & Wound's review of the SRPD line points out that water resistance dropped from the SKX's 200m to 100m and the screw-down crown was replaced with a standard push-pull crown, meaning the SRPD is not ISO dive-certified in the way the SKX was.

The SRPD55 is powered by Seiko's in-house caliber 4R36, an automatic movement with 24 jewels beating at 21,600 vibrations per hour (4Hz· hr basis, i.e. 3Hz) and offering roughly 41 hours of power reserve, per Seiko USA's own product specifications. The movement supports both hand-winding and hacking seconds — the ability to stop the seconds hand when the crown is pulled out for precise time-setting.

That combination of hacking and hand-winding is the movement's headline upgrade relative to the 7S26 caliber that powered the outgoing SKX007. Rescapement notes the 7S26 lacked both features, and Millenary Watches' review of the SRPD55K1 calls the addition "a major upgrade to the new Seiko 5 Sports series." Rescapement also cites improved rate performance over the 7S26, which it describes as typically running 35–45 seconds a day, though it does not give a comparable published spec for the 4R36's own accuracy tolerance.

The movement is visible through a see-through, screw-down exhibition caseback, per Seiko's own listing.

Worn & Wound's review of the SRPD line, which shares the SRPD55's case, describes the case profile as "rather curvy," with gently rounded sides that nestle into the wrist; because the caseback bubbles out beneath the watch, the reviewer notes it settles onto the wrist with a feel thinner than the 13.4mm measurement suggests. Despite the 42.5mm diameter, the review states the watch "works with a ton of wrist sizes" thanks to its comparatively short 46mm lug-to-lug.

Reviewing the SRPD51K1 — a dial/bezel colorway built on the identical SRPD case and bracelet as the SRPD55 — Centre Seconds' Gregory Sze reported the watch "feel[s] like a 39mm watch on the wrist instead" of its stated dimensions, and called it "a very comfortable timepiece to put on day in, day out." Sze rated the polished Oyster-style bracelet as "above average in terms of its build quality" for the price point, though not premium, with a smoothly operating three-fold clasp and push-button release. He also flagged two shared quirks inherited from the SKX design language: the non-screw-down crown requires firm force and gives "a slightly gritty sensation" when wound, and the unidirectional bezel, while smooth-turning with minimal backlash, sits "tiny bit misaligned" relative to the chapter ring.

The SRPD55 designation covers a single black-dial, black-bezel case and dial combination sold on two strap options, distinguished by a K-suffix reference. WatchBase lists the SRPD55K1 on a stainless steel bracelet and the SRPD55K3 on a black NATO strap; both share the same 42.5mm case, 4R36 movement, and 100m water resistance rating.

The SRPD55 was one of 27 references Seiko launched simultaneously in the 5 Sports collection's 2019 debut, per Rescapement, spread across the line's five thematic subcategories. Within the "Sports" grouping the SRPD55 belongs to, sibling references use the same case and movement with different dial/bezel color pairings — for example the SRPD53 (blue dial, red-and-blue "Pepsi" bezel) and SRPD59 (orange dial, black bezel) — while other subcategories such as "Suits" swap in mesh bracelets and dressier dial finishes, according to Bespoke Unit's guide to the collection.

Seiko USA lists the SRPD55's US retail price at $350, though the model has shown as sold out directly through Seiko's own site. Bespoke Unit's guide to the 5 Sports collection places the broader SRPD/5 Sports SKX-style lineup's retail range at roughly $295–$450 depending on reference and strap type, and notes that 5 Sports watches "can often be purchased at a substantial discount off the retail price" through authorized third-party dealers.

The SRPD55 is sold through Seiko's own US and Japan e-commerce sites as well as authorized retailers; the bracelet version (SRPD55K1) and NATO-strap version (SRPD55K3) are listed as separate, individually purchasable references by retailers and by WatchBase.