Seiko 88-5021 – Mechanical stopwatch manufactured in Daini Seikosha (October 1974)

The Seiko 88-5021 is a precision mechanical stopwatch from the Daini Seikosha factory , produced in October 1974 (serial number: 40xxxx – first digit = year, second = month).

It exemplifies the precision, reliability and vertical integration that Seiko demonstrated in the 1970s, even outside the wristwatch segment.

The model belonged to the professional series of hand and sports timers, as used in training centers, laboratories and timekeeping organizations.
The manufacturing quality, the clear dial layout and the robust stainless steel case reflect Seiko's ambition to produce highly precise mechanical timepieces, even after the quartz revolution had already begun.

Historical background

In the 1960s and 70s, Seiko supplied numerous sports federations and timekeeping organizations worldwide with precise mechanical stopwatches.
While Suwa-Seikosha focused on wristwatches, Daini-Seikosha (recognizable by the small lightning symbol ⚡ on the dial) manufactured many of the high -precision analog measuring instruments, including the 88 series.

The 88-5021 stands at the transition from purely mechanical to quartz-controlled timekeeping and is therefore a particularly attractive collector's item today – technically sophisticated, historically significant and typically Japanese in its clear industrial aesthetic.

Design description

The model 88-5021 has a chrome-plated stainless steel case (ACRP) with a large knurled push and winding button and a start/stop button at 11 o'clock.
The silver dial has a fine matte finish and features blue printed second markers in 1/5-second increments as well as a black 60-second scale.

At the center: the large chronograph seconds hand, complemented by a small minute counter at 12 o'clock (up to 15 minutes).

The typographic clarity, symmetrical design and lack of decorative elements emphasize the technical functionality – a prime example of Japanese “form follows function” design from the 1970s.

Technical data

• Brand: Seiko
• Model: stopwatch
• Reference: 88-5021
• Factory: Mechanical hand-wound movement (caliber 88)
• Production date: October 1974
• Manufacturing site: Daini-Seikosha ( ⚡ Lightning symbol on dial)
• Housing material: Chrome-plated stainless steel (ACRP)
• Diameter: 48 mm (excluding push button)
• Height: approx. 14.7 mm
• Dial : Matte silver with blue minute track and black 1/5-second scale
• Counters : Central chronograph seconds, minute counter (0–15 min)
• Pusher : Start/Stop at 11 o'clock, zeroing via winding crown
• Glass : Mineral glass
• Back : Engraving “SEIKO 88-5021 / ACRP / JAPAN”
• Origin : Made in Japan

functions

• Manual winding (mechanical, mainspring drive)
• 1/5-second division
• Central chronograph seconds
• Minute counter up to 15 minutes
• Start/Stop via top button
• Zero setting by pressing the crown

Condition & Special Features

• Very good condition with only slight signs of wear.
• Original dial and hands, unaltered
• Mechanics fully functional, precise reset
• Engravings on the case back are clearly legible.
• clean glass

This Seiko 88-5021 is an authentic instrument from the Daini Seikosha workshop , built in a time when precision was still achieved purely mechanically.
A piece of professional Japanese watchmaking history that appeals to both technology and design enthusiasts.

Warranty (used)
This is a used item . The limitation period for claims based on defects ( statutory warranty ) is 12 months from delivery .

Notice
As this is a used watch, water resistance cannot be guaranteed . To protect the movement, the watch should not come into contact with water or moisture.