Citizen introduced the Promaster series in 1989.
The series included watches in the categories of Land, Marine, and Sky. One slogan they used to describe these was: "Citizen Promaster watches are the ultimate choice for professionals and serious enthusiasts. Venture beyond experience".
The symbol chosen for the Promaster series is shown above, and is very similar to the pheon used to mark British military equipment.
One famous user was Ray Mears, and he used a Promaster Eco-Drive model with a mono bloc tonneau case.
This article deals with the type of watch which he wore with a similar dial and a mono bloc tonneau case, introduced in 1999 and ceasing production in about 2007.
Other rear entry and mono bloc tonneau case Promaster watches exist with varying dials , but are not covered in this article.
Eco-Drive and the 7878 movement
The technical platform that made the Eco-Drive possible was the caliber 7878 movement. This movement was the first light-powered movement with the solar cells mounted under the dial.
Previous light powered watches from Citizen and other manufacturers had the solar cell(s) mounted directly on the dial. The under dial innovation was enabled by marked improvements in thin film solar cells, which, by the early 1990s had become significantly more efficient. By locating a sufficiently translucent dial material over the now more efficient solar cells, enough light could pass through the dial face to power the movement. Although the Eco-Drive caliber 7878 movement solar cells remained slightly visible through the dial, the physical styling of the light-powered watch was no longer constrained by visible solar cells.
To store electrical energy the first Eco-Drive movements employed titanium lithium-ion rechargeable or secondary batteries. This battery type became available in the early 1990s, enabling an Eco-Drive 7878 movement to run 180 days on secondary power before requiring recharging via light exposure – a marked improvement in energy storage over previous light-powered watches. The movement also featured an "insufficient recharging" indicator. The accuracy of the quartz movement was stated as within ± 20 seconds per month at a normal temperature range.
If deprived of light for an extended amount of time, some later models could hibernate, and the hands of the watch stop moving, while the internal quartz movement continues to track the time accurately. When eventually exposed to light, the hands will then move to the correct position and resume timekeeping as usual. Thus, if you leave your watch in a drawer say for 4 months, then take it out and expose it to light, it will show the correct time immediately.
According to reports from Citizen Watches, experiments have revealed that the solar cells and secondary battery used in Eco-Drive watches will last for up to 10 years. They further state that the lubricants used in constructing these watches are built to assist with longevity, as the oil will not harden or evaporate, even over 20 years.
Some users may disagree with this.
The Promaster "Ray Mears" series
The 1999 Citizen catalogue shows the initial models in what has become known as the Ray Mears series.
The two smaller models are PMU56-2481 and PMU56-2485, selling for 33,000 yen and 36,000 yen respectively.
This article will deal with these first.
7878 - H16714 TA or PMU56-2481
This watch is a black dial version, with a small diameter, featuring the Caliber 7878 movement.
This is the JDM version with the Promaster symbol at the top beneath Citizen, and Eco-Drive in italics at bottom.
It features a solid one-piece Duratect titanium mono bloc case, extra-thick sapphire crystal, is antimagnetic, shockproof and 200m waterproof.
Duratect is a process where the surface is hardened, to protect the watch body from small scratches.
The crystal is spherical sapphire glass (non reflective coating) where magnesium fluoride is deposited on the glass
Case diameter is 38mm including crown, with a length of 40mm lug to lug (tip to tip of lugs), and 10mm thick with strap width 18mm
It came on a kevlar strap with all titanium hardware.
The dial features a triangle at 12, rectangular indices at 6 and 9, a date window at 3, and thick lumed numerals elsewhere.
Below on a replacement NATO strap.
The image below shows the original kevlar strap.
At 6 the dial reads Eco-Drive , WATER 20 bar RESIST , TITANIUM.
The case back is slightly lipped at the edge.
The text on the rear of the case reads:
Eco-Drive, CITIZEN WATER RESIST , (model number) , ANTIMAG. 16000 , TITANIUM, 7878-H16714 TA , GN-4W-UL JAPAN
Below is an image of the luminous properties of the watch, with the second hand "bulb" showing, rather than the pointer.
A blue dial version was also available.
7878-H21882 TA or PMU56-2485
The more expensive model of the small series was the Yellowstone National Park series watch, again with Caliber 7878 Eco-Drive.
Here is the advertisement with both model numbers shown.
It came on a yellow kevlar strap with all titanium hardware, a yellow sweep second hand, and the dial marked with the Promaster symbol, Yellowstone National Park (in yellow) , WR 20 bar at 6 o'clock.
This is the case back of this model, engraved with Yellowstone National Park, and an image of the mountain and a bison.
7878-H30351 TA or PMU56-2487
This is the Calibre 7878 Citizen Promaster “Tough” Ecodrive, special Mt.Cook/Aoraki Commemorative edition, (case marking: (7878-H30351 TA)). Titanium case, blue face, blue leather strap, domed sapphire crystal. Mid-size 34mm diameter not including crown.
Case back engraved with Aoraki, Mount Cook.
7828-H09971 TA or PMU56-7371 and PMU56-7376
This was also model PMU56-7371 on a kevlar band and PMU56-7376 on a titanium bracelet, as seen in the 1999 advertisement above. The caliber was now the bigger 7828 Eco-Drive, and the watch was bigger.
We have seen above that the bigger PMU56-2371 sold for 33,00 yen. The titanium bracelet version, PMU56-2376 sold for 50,000 yen.
The kevlar strap versions had a plate on which personal data could be engraved. After purchase, if you sent the necessary information on the enclosed application postcard, you received a titanium band engraved with 'name', 'nationality', 'blood type' and 'date of birth'
PMU56-2377 and PMU56-2487 in the above image under personal data refer to the Mount Cook version.
Ray Mears has given his name to the 7828-H09971TA, it being seen as he wore it often in his outdoor TV shows, as it was a titanium cased, bomb proof, rugged, outdoor, watch. It was labelled Promaster, Tough.
The dial is identical to the smaller version, but green dial versions existed.
The watch has a Duratect titanium mono bloc case (no case back, the movement is front loaded). Duratect is 4 times harder than untreated titanium. Dimensions are 40mm diameter, 11mm thick, 20mm lugs. The crystal is a domed sapphire with anti reflection material on the inside. The crown is screw down and the watch is rated to 200m. Lugs are recessed slightly under the bezel which means many straps fit with minimal gap - it comes on a canvas strap.
The green dial model is shown above.
The titanium bracelet model came at 50,000 yen.
The text on the rear of the case is:
Eco-Drive CITIZEN WATER RESIST ANTIMAG. 16000 TITANIUM 7828-H09971 TA GN-4W-UL JAPAN
The caseback shows the model number, and that the watch has with the early 7828 Eco Drive movement, The code GN-4W-UL means monobloc case, upper opening, L-shaped gasket. The early movements have a 6 month reserve and none of the features of later movements such as parking the second hand to conserve power in the dark, and a perpetual calendar.
Later versions were referred to as PMU56-2373 , AP0600-01E with the Promaster symbol moved from 12 to 6, and fewer words on the dial. The case back remained the same.
Now the Promaster symbol is at 6 o'clock and beneath is simply, WR 200 TITANIUM
Below is a blue dial version of the AP0600-01E
The screw down crown was knurled and not marked with the Promaster symbol.
The kevlar strap versions had a plate on which personal data could be engraved.
7828-H21963TA or PMU56-2375
Yellowstone National Park commemorative model, on yellow strap.
Yellow second hand.
7828 H30369 TA or PMU 56-2377
Aoraki or Mount Cook commemorative edition also with the bigger Caliber 7878.
Blue leather strap, but sometimes seen on a titanium bracelet.
7828 H09980 TA
A black (PVD) model marked base titanium on the case back. This had either a kevlar strap, or a black titanium bracelet.
Case back, kevlar strap.
Black titanium strap.
Or a gold model.
E766-T000894 or PMT56-2711 and PMT56-2713
PMT56-2711 is the blue dial Perpetual calendar Cal e766 E766-T000894 TA model and PMT56-2713 is the black dial version. These versions feature the titanium bracelet, and were 41mm in diameter.
PMT56-2712 is the blue dial Perpetual calendar model on a kevlar strap, and PMT56-2714 is the black dial version on a kevlar strap.
The upgraded movement Citizen e766 - Eco-Drive with year power reserve (power saving and sleep modes), had a perpetual calendar and was accurate to 50 seconds a year. The dial was similar to other "Ray Mears" dials, except that the rectangles at 6 and 9 were replaced with pointed tapered trapeziums. The lumed numerals were all chrome trimmed. The second hand had an open bulb with a red pointer.
On this model, the minute hand moves every 15 seconds which is another power-saving feature.
It was discontinued in 2004.
This watch had :
Crystal: Domed sapphire
Case: 41mm Duratect Titanium (one-piece monocoque construction)
Bracelet: Duratect Titanium (800 vickers on the hardness scale with solid end links, push button with flip over double clasp diver's extension).