Omega Speedmaster Mark IV

The Squircle-Shaped Speedy

Omega launched the automatic Speedmaster Professional Mark IV ref. 176.0009 In 1973. This model goes against the grain of the standard Speedmaster design. The Mark IV has a cushion-shaped stainless steel case, following in the footsteps of the Mark II from 1969. The surfaces of the case are brushed, while the narrow edges are polished.

Today, the Speedmaster Mark models are considered somewhat unconventional. Interestingly, these cushion-shaped watches were actually ahead of their time, as this case shape only started to gain traction years later in the 1980s. Omega only produced the Speedmaster Mark IV until 1974, at which time it was replaced by the Mark 4.5 ref. 176.012. Although the successor model differs in terms of movement and dial design, Omega still considers it to be part of the Mark IV series.

Reasons to Buy the Omega Speedmaster Mark IV and 4.5

• Extraordinary Speedmaster design
• Mark IV: Omega's first chronograph with an automatic movement
• 24-hour display for travelers
• Relatively affordable

Details & Prices: Speedmaster Mark IV & 4.5

The Speedmaster Professional Mark IV measures 41 mm in diameter and features a black dial. You will notice that this timepiece only has two subdials: a 12-hour counter at 6 o'clock and a combined small seconds and 24-hour display at 9 o'clock. The 24-hour hand is triangular and sits on a small, round plate that makes a full rotation every 24 hours. This subdial clearly indicates whether it is day or night in the second time zone via gray shading between 6 and 18. The Mark IV also has a date window at 3 o'clock. Another interesting detail is that the chronograph minute and second hands are located in the center of the dial. The tachymeter scale is printed on the inner side of the mineral crystal protecting the dial.

Inside the case, you'll find the automatic Omega 1040 caliber. This movement is based on the Lemania 1340, which can also be found in many other chronographs from various brands such as BWC, Enicar, and Tissot. The most significant modification Omega made to the 1340, and possibly the only modification, was the addition of a 24-hour counter. The balance of the caliber 1040 ticks at 28,800 vph, and the power reserve clocks in at about 44 hours. You can pair this watch with a three-piece link stainless steel bracelet or a sporty strap made of Corfam, a synthetic leather.

Pre-owned, the Speedmaster Professional Mark IV ref. 176.0009 sells for around 1,600 USD on Chrono24.

Differences & Prices: Speedmaster Mark IV and Mark 4.5

Produced between 1974 and 1986, the Speedmaster Professional Mark 4.5 differs from its predecessor in some key details, mainly movement and dial design. Unlike the Mark IV, which is powered by the Omega 1040, the Speedmaster Mark 4.5 uses the caliber 1045, which is based on the Lemania 5100.

Contrary to the Speedmaster Mark IV, which only has two subdials, the Mark 4.5 has three. The 12-hour counter sits at 6, the small seconds at 9, and the 24-hour display at 12 o'clock. The day of the week and date displays are at the 3 o'clock position. The chronograph minute and second hands are positioned in the center of the dial, alongside those for the normal hours and minutes. Expect to pay around 2,900 USD for a pre-owned Speedmaster Mark 4.5.