The Quartz LC SEIKO World Time "PAN AM"

Model No. M158-5000 and M158-5009

In 1977 SEIKO started a new line of digital World Time watches using the latest quartz and LCD technologies.

In 1977 the SEIKO World Time was completely re-imagined using the latest in quartz and liquid crystal technology. The result was a thoroughly modern, Digital LC (Liquid Crystal) World Time offered in three varieties.

The Stainless Steel M158-5000, intended for Japanese Domestic and International markets

The Stainless Steel M158-5009, intended for North American markets

The Gold-tone/Gilt M158-5009, intended for North American markets

Key Statistics
Top-Line Sales Info
General Information
Dial Features
The Case
Measurements
The Case Back
Dial Frames
Original Bracelets
Production Numbers
Resale Value
Other Resources
Video on how to use the watch
Related Articles

Key Statistics

37mm

Watch Case Size w/o Crown

40mm

Lug to Lug Measurement

Common

Rarity Index Among Cataloged Examples is 2.6 out of 10

57

Total Examples Cataloged

30.0%

Percentage of all Cataloged Digital Examples

Top-line Sales Info

37mm stainless steel case
40mm lug to lug
World Time complication: keeps time in 29 times zones around the world and accounts for both time and date of each
GMT Multi-Mode: Toggle between local and any other time zone with the click of a button
Perpetual calendar, pre-programmed to account for varying length months and leap years until 2009
Built-in illumination system
+/- 10 seconds per month accuracy (2 minutes per year)
Waterproof to 30m (100ft)
HARDLEX mar-resist crystal
Offered in Gold-tone w/ gilt dial frame and stainless steel w/ black dial frame
MSRP: 45,000 YEN / $215 USD in Stainless Steel
MSRP: $275 USD in Gold-tone

General Information

This watch came in two model numbers, with differing dial frames and bracelets. The M158-5009, intended for the North American market, had abbreviated city names and hour offset indicators and was sold on a 3 link bracelet. The M158-5000 on the other hand, was intended for sale outside of North America, with full city names, no hour offset indicators and was offered on a single link style bracelet.

The "M" at the start of the model number was used to indicate that this watch was one of SEIKO's multi-function watches. Later watches in this series have model numbers starting with "A", indicating they include an alarm complication, an option this first iteration did not offer.

Both models were offered in stainless steel. Based on the image data collected as of this writing, it appears that only the M158-5009 was offered in gold-tone.

It is said that this watch was popular among pilots of the time, both for its world time and GMT features, as well as the lemon colored LCD, which was easy to read in low light. It is commonly referred to as the SEIKO PAN AM.

It should also be noted, that while quartz and digital watches eventually became synonymous with cheap, mass produced, and unserviceable, that was not the case with these early digital watches. Not only did they sell for a significant premium over the outgoing mechanical equivalents, the components used were robust and high quality for the day. As an indication, the outgoing mechanical 6117-6400 had an MSRP of $69 USD ($99 in gold-tone metal) in 1976, whereas this digital replacement had a list price of $215 USD ($275 in gold-tone) in 1977.

More than 40 years later, examples of these watches can be found running with the same precision and legibility they offered when new.

Dial Features

The liquid crystal display includes a day/date complication and a quick toggle to change between a reference time and the local time, which is a digital equivalent of a GMT feature. Here is an overview of the dial features transplanted from an SEIKO catalog page of the North American version.

Home Time Mode features continuous readout in hours on a 24-hour basis, minutes, seconds, day and date. Calendar is pre-programmed for leap years, 28, 30 and 31 day months until the year 2009. Built-in illumination system.

Greenwich Mean Time is displayed at the push of a button.

World Time symbol appears when crown is pushed, indicating World Time Mode is in operations.

Each time button is pushed, Zone Marker moves to next city and time zone and displays the correct hour, minutes, seconds, day and date.

The Case

The case has 3 buttons, all on the right side of the case

Underside of hooded lug profile - bottom side

Underside of hooded lug profile - top side

Measurements

Here are approximate measurements.

The bracelet at its widest point measures about 21.4mm

The spring-bar tubes are slightly slimmer than the bracelet at 19.7mm wide

The bracelet tapers to 15.5mm wide at the clasp

The Case Back

The case back design and wording is similar for both model numbers and color options. There is a screw down battery replacement door, and the case back itself is of the snap-on variety.

The M158-5000 case back
S/N, SEIKO, JAPAN A, WATER RESIST - G ST. STEEL M158-5000

The M158-5009 in Stainless Steel case back
S/N, SEIKO, JAPAN A, WATER RESIST - G ST. STEEL M158-5009

The M158-5009 in Gold-tone metal case back
S/N, SEIKO, JAPAN A, WATER RESIST - G BASE METAL TOP ST. STEEL BACK M158-5000

Note the case back has a teardrop shape that leans slightly to the right when viewed on center.

Dial Frames

Here are the three different dial frames.

Black dial frame from M158-5000, including full city names and markers in white and orange.
Dial Code: M158-5000 T

Black dial frame from M158-5009, with abbreviated cities and hour offset markers in white and blue.
Dial Code: M158-5029 T

Gilt dial frame from M-158-5009, with abbreviated cities and hour offset markers in black and orange.
Dial Code: M158-5029 T

The 5000 is marked QUARTZ vs QUARTZ LC on the 5009.

Original Bracelets

The M158-5000 Bracelet

The Japanese / International version of the M158 was offered on a modern, single link design bracelet. A sliding clasp allows the bracelet to be resized without removing links.

The bracelet clasp is adjustable on the bracelet, similar to the clasp for a leather strap

The sliding / adjustable side of the clasp

The under side of the links, end links marked XAS020

Side profile, with the excess bracelet tucked under the clasp, against the wrist

The M158-5009 Bracelet

The M158-5009 was offered on a three link bracelet in stainless steel or yellow/gold to match the watch case.

A closer look at the link adjustment pins

The underside of the link that connects to the clasp

The end links / spring-bar tubes are marked Z-129

Signed SEIKO clasp - SQ stands for SEIKO Quartz

The interior of the clasp is signed: All Stainless Steel, Japan Z

Production Numbers

Based on the image data collected to-date, this series appears to have been produced from April 1977 through January 1979. These models use a 6-digit serial number scheme, allowing for up to 9,999 watches per production month/year. Assuming a 21 month production run, this allows for a max production of 209,979 watches, with a minimum production of 45,020 based on current image data.

JDM (M158-5000) watches currently account for 33.93% of cataloged examples. North American Market (M158-5009) watches currently account for 66.07%.

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. $800+ 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. $600 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. $300 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". $200 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. $100 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. $50 USD