Omega Speedmaster Calibre 321 39.7mm steel on steel

Having been a part of all six lunar missions, the legendary OMEGA Speedmaster is one of the world’s most iconic timepieces. This model has reprised the famous Calibre 321, which was an important part of the Speedmaster’s original space history.The 39.70 mm case is in stainless steel and is inspired by the same 3rd generation style worn during America’s first spacewalk in 1965. There is also a bezel ring in polished black ceramic [ZrO2] with the tachymeter scale in white enamel.The black step dial features familiar Moonwatch hands, a vintage OMEGA logo, as well as a small seconds sub-dial, 30-minute recorder and 12-hour recorder along with a central chronograph hand. Through the sapphire-crystal caseback, you can see the Calibre 321 inside.
Features
Chronograph
The chronograph function is a mechanism for measuring time intervals. A chronograph watch can therefore be used to time events while displaying the time like any traditional watch.
Small seconds
A hand on a sub-dial which tracks seconds typically it completes a full rotation in one minute.
Tachymeter
A tachymeter watch has a function for measuring speed. It is a chronograph with a graduated dial on which speed can be read in kilometres per hour based on a 1000 metre distance.
Transparent caseback
A transparent caseback – frequently made of sapphire – makes it possible to see the movement inside the watch.
Technical Data
Reference
311.30.40.30.01.001
Between lugs 19mm
Lug-to-lug 48.0mm
Thickness 13.7mm
Case diameter 39.7mm
Case
Steel
Dial colour Black
Crystal
Scratch-resistant sapphire crystal with anti-reflective treatment inside
Water resistance
5 bar (50metres / 165 feet)
Total product weight (approx.)
128 g
Calibre: Replica Omega 321
Movement Type Manual-winding
Power reserve 55 hours
Case Measurements
1. Between lugs This measures the space where a strap or bracelet would be placed.
2. Lug-to-lug
This is the full length of the case, from the top lugs to the bottom lugs.
3. Case diameter This is the full width of the watch’s case, excluding the crown and pushers.
4. Thickness When viewed from the side, this measures from the base of the watch to the surface of the glass.
Bracelet
Material Steel
Type of Clasp Foldover clasp