Citizen Record Master RMOS 2901-T


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Citizen Record Master chronographRef. RMOS 2901-T

It marked the debut of the Citizen in producing chronograph-type models. Surprisingly, it turned out to be the sole hand-wound chronograph movement ever manufactured by Citizen.

Quick facts

Citizen website

Brand: Citizen
Model: Record Master chronograph
Reference: RMOS 2901-T
Year: 1968 December
Case: Stainless steel, 38mm
Caliber: Citizen 5701, manual-wind

What about it

A stunningly elegant yet sporty chronograph featuring a unique manual-winding movement, exclusively available during December '68.

The Citizen Record Master, introduced in mid-1967, marked the inception of the first chronograph-type production model by the Citizen watch company. Remarkably, it remains the sole hand-wound chronograph movement ever manufactured by Citizen. Although its production spanned only five years, from 1967 to 1972, an unexpectedly vast array of diverse variants emerged during this brief period.

The model RMOS 2901-T was released around December 1968, in fact all examples seen had this one month of production. The movement is the second iteration of Citizen's only hand winding chronograph movement, Citizen calibre 5701. It has 21 jewels and beats at a slow 18,000bph. Elapsed time can be measured for one minute. The user can start/stop and reset the chronograph as well as flyback (reset while running). The date is not quick-set but is changed by advancing the hour hand past 12.

Read more on Henry Quarmby's site

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Citizen Record Master RMOS 2901-T

About this variant

The hands and applied hour markers are in polished stainless steel. The crystal is mineral, the crown is marked "C". The case is one of the larger Record Master designs. The 4-570031T also uses this case it measures 38mm exc crown and 43mm lug to lug. Lug width is 18mm. Thickness is approx 13mm. The case back has first 3 numbers of the serial relate do the manufacture date. The bracelet is made up of slightly curved brushed elements separated by polished bead elements. It is a very common bracelet style in Citizen watches of this era. I am not aware of any other bracelet style for this model. The clasp is unsigned.

Citizen Record Master RMOS 2901-T
Citizen Record Master RMOS 2901-T Citizen Record Master on Henry Quarmby site Citizen Record Master movement. Photo from Citizen Record Master black variant. Photo from


Availability: very rare
1 available

Pricing: 2,000+ €
in good condition
(Dec 2023)



Found few website where you can find some info.

Henry Quarmby's site

VCW site