Studio Underd0g 04SERIES Calendar: Britain’s Most Interesting Affordable Complication

There is a particular kind of watch that the industry rarely produces well. It sits in the gap between a simple three-hander and the kind of calendar complication that costs more than a second-hand car. Filling that gap with something genuinely interesting, well-made, and priced at £750 is a tall order. Studio Underd0g, the British watchmaker founded by Richard Benc in 2020, has had a go at it with the 04SERIES Calendar, and the result is worth paying attention to.

What Studio Underd0g Actually Is

Before getting into the watch itself, it helps to understand where the brand comes from. Rich Benc launched Studio Underd0g with a deliberately unusual brief: build serious watches that do not take themselves too seriously. The name reflects the brand’s position as a design-led newcomer in a world dominated by Swiss heritage brands. The “0” in the name is a nod to gaming culture, where players swap standard characters for distinctive ones to stand out from the crowd. It is a small detail that says quite a lot about how the brand thinks.

Since 2020, the company has built a following through colourful chronographs, smart collaborations, and a philosophy of assembling every watch by hand in Great Britain. Each piece is put together by a single watchmaker, whose initials appear on the accompanying paperwork. That is a meaningful commitment for a brand at this price point, and it is not something most watch companies at this level bother with.

The 04SERIES Calendar is a first on two counts. It is the brand’s first automatic watch, and it is the brand’s first calendar complication. Neither of those is a small step.

The Complication Itself

The 04SERIES Calendar packs three complications into a 37mm or 38.5mm case. The first is a retrograde date pointer, which sweeps across an arc and snaps back to the beginning at the end of each month. The second is a moonphase display. The third is the detail that most people will talk about: a weekend indicator.

The weekend indicator uses chamfered, CNC-cut windows positioned next to the static date numbers around the outer edge of the dial. An underlying disc rotates when you manually set it at the start of each month, using the first crown position. That disc highlights all Saturdays and Sundays for the entire month at once, showing coloured markers through the relevant windows next to those dates. The whole month is set in one go, rather than advancing dynamically day by day.

It is a genuinely clever visual idea, and there is nothing quite like it at this price. For context, the Krayon Anyday achieves a fully automatic version of a similar concept, but Krayon charges significantly more for the privilege.

There is one practical point worth being clear about. The weekend indicator is not automatic. At the start of each month, the wearer sets it manually using the first crown position, with the second (outermost) crown position reserved for setting the time. For some buyers that will be a minor task. For others it will become part of the ritual of wearing the watch.

The date is set via a concealed pusher at 2 o’clock. The moonphase corrector sits at 8 o’clock. The layout is clean, and the retrograde mechanism means the date pointer does not interfere with the moonphase display, which is a thoughtful piece of dial architecture.

The Movement

The movement is where the real story is. Studio Underd0g worked with Tianjin Seagull, one of China’s most established movement manufacturers, to develop a bespoke calibre over two years. The resulting ST-2115B is an automatic movement running at 28,800 vph with a 42-hour power reserve, hacking seconds, and 34 bespoke components designed, tooled, and tested specifically for this watch. It is visible through a sapphire caseback.

Seagull is worth a brief introduction for anyone unfamiliar with the name. The Tianjin Sea-Gull Watch Group has been producing mechanical movements since 1958 and is currently China’s largest watch manufacturer by volume. Its ST19 chronograph movement has been used by respected Swiss brands, and its ETA-equivalent calibres compete credibly with Sellita on quality. Working with Seagull is not a compromise. It is a sensible choice for a brand that wants a genuinely developed, bespoke movement without paying Swiss manufacture prices.

The Case and Dial

The case is 316L stainless steel with a flat stepped bezel, polished bevels, and thin lugs. At 10.5mm thick excluding crystals and 44.5mm lug to lug, it is wearable on a range of wrist sizes. Including the double-domed sapphire crystal, overall thickness reaches 13.5mm. Water resistance is 50 metres, appropriate for a dress-adjacent calendar watch. A screw-down display caseback shows the movement.

Four dial colourways are available at launch, each inspired by views from the studio window. Cloud10 is a light silvery-blue. Arabian Sky is a golden bronzy-salmon tone. Shepherd’s Delight is red. 0vercast is a dark grey-blue. Hours and minutes are shown by leaf-shaped hands. The dial uses a chapter ring rather than applied numerals, keeping the surface clean enough for the complications to breathe.

Straps are made by The Strap Tailor and taper from 20mm to 16mm with quick-release spring bars. A steel mesh bracelet is available as an option.

The Price and What It Means

At £750 (USD 1,100 / EUR 800 / CHF 800), the 04SERIES Calendar occupies a space that very few brands are willing to touch. Calendar complications typically start at several thousand pounds from established names. The moonphase alone usually adds a substantial premium. The weekend indicator is genuinely novel at any price. Getting all three into a British-assembled watch with a bespoke movement, at this price, is an achievement worth acknowledging.

The watch is available from 17 November 2026 via underd0g.com and by appointment at The D0ghouse in Maidenhead.

For anyone who wants a calendar watch that does something genuinely different, without spending the equivalent of a family holiday to find out, the 04SERIES Calendar is a serious contender. It is the kind of watch that makes you wonder why more brands have not tried something similar, and then realise the answer is that it is actually quite hard to do well.

The 04SERIES Calendar is available from 17 November 2026 at underd0g.com.