The SEIKO World Time "Alarm"

Model No. A358-5000 and A358-5009

In 1979 SEIKO introduced a new line of digital World Time watches replacing the iconic PAN AM

In 1979 SEIKO introduced two new digital world time watches, the A239 and this A358. This A358 model was likely the direct replacement of the M158 PAN AM, and is often overlooked in the digital generation.

The Stainless Steel A358 with Black Dial Frame

The Stainless Steel A358 with White Dial Frame

The Stainless Steel A358 with Gray Dial Frame

The Gold-tone A358 with Black Dial Frame

This new version made several significant changes to the design of the outgoing M158. The case was narrowed to just 33.5mm wide ( a reduction of 3.5mm), an alarm function was added with a prominent speaker grill pushing the dial down and off-center from top to bottom. The pull out crown was done away with, replaced with 4 push buttons, one in each corner. Additionally, the now iconic yellow LCD of the M158 was replaced with a standard gray module, and the dial frame color choices were expanded, with black, gray, white and gold colored options. Finally, the case back was also changed, from a snap on type with dedicated battery hatch to a one-piece quarter turn screw down setup.

The bracelet on all A358 models was nearly identical to the M158-5000 JDM bracelet, with small difference between the JDM (A358-5000) and US market (A358-5009) versions, mainly in the clasp.

Key Statistics
Top-Line Sales Info
Measurements
Dial Frames
Bracelets
Production Numbers
Resale Value
Other Resources
Related Articles

Key Statistics

33.5mm

Watch Case Size w/o Crown

39.5mm

Lug to Lug Measurement

Uncommon

Rarity Index Among Cataloged Examples is 7.4 out of 10

27

Total Examples Cataloged

14.2%

Percentage of all Cataloged Digital Examples

Top-line Sales Info

33.5mm case (not including buttons)
39.5mm lug to lug
28 selectable Time Zones
Home time and calendar display: 12-hour Digital Display System showing hour, minute, second, AM/PM, date and day of the week, month and year.
World time and calendar display: 12-hour Digital Display System showing the hour, minute, second, AM/PM, date and day of the week for almost all parts of the world are displayed.
Alarm Display: (a) Home time alarm : In the home time display, it can be set to operate at any desired minute and hour. (b) World time alarm : In the world time display, it can be set to operate any desired minute and hour of the designated area every day.
Display Medium: Nematic Liquid Crystal, FE-Mode
Time micro-adjuster : Trimmer condenser system
+/- 10 seconds per month accuracy (2 minutes per year)
Offered in Stainless Steel and Gold-tone versions
MSRP: 32,000 YEN / $Unknown USD in Stainless Steel
MSRP: Unknown YEN / $Unknown USD in Gold-tone

Measurements

Here are approximate measurements.

Case width, excluding buttons is around 33.5mm

Dial Frames

Here are the four different dial frames.

The black and yellow dial frame, code A358-500AT, for SGP case

Original Bracelets

XAS110

The XAS110 bracelet was matched with the A358-5000 models, in both stainless steel and gold-tone finishes. The lug width at the spring bars is 18mm, with the bracelet itself tapering from 20mm to 14.5mm at the clasp.

This bracelet feels slightly more substantial than the B487, but looks identical save a different clasp design.

The adjustable buckle underside, signed SEIKO STAINLESS STEEL/L

B487

The B487 bracelet case fitted on the A358-5009. It looks nearly identical to the XAS110, except for the clasp, which is smaller and has an overall different shape. The lug width at the spring bars is 18mm, with the bracelet itself tapering from 20mm to 14.5mm at the clasp.

The bracelet code is stamped on the underside where the spring bars connect.

The top and side profile of the clasp. XAS110 at top for comparison to B487 (at bottom).

The underside of the buckle, marked SEIKO ALL STAINLESS STEEL JAPAN B-L

The top and side profile of the buckle. XAS110 at top for comparison to B487 (at bottom).

Production Numbers

Based on the image data collected to-date, this series was produced from at least February 1979 through at least February 1980. These models use a 6-digit serial number scheme, allowing for up to 9,999 watches per production month/year. Assuming a 13 month production run, this allows for a max production of 129,987 watches, with a minimum production of 30,729 based on current image data.

Resale Value

Please note:

This scale is a derivative of the Hagerty Classic Car Condition Rankings, adapted for watches. It is an attempt to keep it simple. They explain it really clearly here (albeit in car terms): Car Conditions: What The Numbers Mean.
Almost no one owns or has even seen a condition 1 example of this watch in at least a few decades. Most of what is sold online today are condition 4 and 5 watches - if you think you have a gem, it is most likely a 3.
While many enthusiasts spend inordinate amounts of time chasing down the best deal, digging through the dark corners of the internet, local antique shops and estate sales, and are ok fixing things up themselves... a lot of others would like to just know what a clean example is worth from a reputable source - that's what these are. Think of them as the price you would expect to pay if you saw one of these under the glass at your favorite local watch shop.
All values assume OEM parts or all original examples. After market dials, mismatched bracelets etc will reduce the value, in some cases substantially. For example a non-original bracelet can reduce the overall value by 10-20%, a non-original dial may reduce resale value by 80% or more.
Finally, gold-tone variations (these are not gold plated, but rather gold colored base metal) command a much lower resale value, from 50% to 80% less than equivalent examples in stainless steel.

Rank	Description and Value
1	Condition 1 EXCELLENT A perfect original (NOS) that has been professionally serviced and where all components are functioning as new; also a watch that has been restored to current maximum professional standards of quality in every area, showing no signs of wear; a 95-plus point show piece that isn't worn. $500+ USD
2	Condition 2 FINE Well-restored or a combination of superior restoration and excellent original, where any replacement parts are strictly OEM; also, an extremely well-maintained original showing very minimal wear, or NOS that has not been professionally serviced. $300 USD
3	Condition 3 VERY GOOD Completely operable original or "older restoration" showing wear; also, a good amateur restoration, all presentable and serviceable inside and out. Plus combinations of well-done restoration and good operable components or a partially restored watch with all parts necessary to complete a restoration and / or valuable NOS parts. $200 USD
4	Condition 4 GOOD A wearable watch needing no work to be functional; also, a deteriorated restoration or a poor amateur restoration. All components may need restoration to be "excellent", but the watch is usable "as is". $100 USD
5	Condition 5 TO RESTORE Needs complete restoration; may or may not be running, but isn't rusted, wrecked or stripped to the point of being useful only for parts. $50 USD
6	Condition 6 FOR PARTS May or may not be running, but is weathered, wrecked and/or stripped to the point of being useful primarily for parts. $20 USD