Back in 2016, Hublot unveiled the Big Bang MECA-10, which featured an innovative in-house movement with a generous 10-day power reserve. While the original MECA-10 watches were properly sizable creations that featured a 45mm rendition of the Big Bang’s signature case, Hublot has created a smaller version of the MECA-10 as one of its releases for LVMH Watch Week 2025. Based upon an optimized and re-engineered version of the Swiss brand’s advanced 10-day caliber, the new Hublot Big Bang MECA-10 42mm features a noticeably more compact profile, and it makes its debut appearance in three different case materials.

Hublot created a desk clock version of the MECA-10 in 2020, although the new 42mm Big Bang MECA-10 watches take this concept in the complete opposite direction, with their reduced dimensions mirroring current trends for smaller timepieces. At the time of launch, the Hublot Big Bang MECA-10 42mm series spans three models, with each one appearing in a different material. The entry-level option is the ref. 444.NX.1170.RX, which features a case crafted from brushed and polished titanium. Meanwhile, the premium version is the ref. 444.OX.1180.RX that swaps out titanium for Hublot’s proprietary 18k King Gold alloy, which offers a warmer hue than traditional rose gold. The third model from the inaugural trio is the ref. 444.QN.1170.NR, which is rendered in Frosted Carbon (a variation of forged carbon with a matte finish and an asymmetric pattern running throughout its structure), and it represents the first standard-production Big Bang watch made from this material.

The case of Hublot’s new 42mm MECA-10 models closely adheres to the familiar blueprint of the Big Bang collection with a multi-component structure held together by the brand’s H-shaped screws. Measuring 42mm in diameter by 13.9mm thick, the new Hublot Big Bang MECA-10 watches represent a noticeable reduction in size compared to the original 45mm Big Bang MECA-10 models, and rather than featuring a micro-blasted finish across their case components, the titanium and King Gold models both have linear brushed surfaces set against small high-polished accents. Just like their larger siblings, the Big Bang MECA-10 42mm watches have sapphire crystal fitted to their bezels and display-style casebacks, and water resistance for the trio comes in at the same 100 meters that is offered by their 45mm counterparts.

In order to accommodate the reduced case profile of the Big Bang MECA-10 42mm, Hublot needed to completely re-engineer its 10-day movement, and this results in a slightly revised display compared to what can be found among the larger 45mm models. Similar to many Hublot watches, the Big Bang MECA-10 series forgoes a dial in order to showcase its party-piece movement, and the various elements of its display are directly integrated into the movement’s structure. A pair of centrally-mounted hands displays the time, while the running seconds are represented by a sub-dial at 9 o’clock. However, the power reserve indicator has been streamlined on the new 42mm Big Bang MECA-10 models, and it now appears as two superimposed discs at 3 o’clock, rather than being positioned on a separate gear at the 6 o’clock location like the 45mm models.

The open-worked display of the Hublot Big Bang MECA-10 42mm fully reveals the mechanics of the model’s internal movement, and the bridges of the calibers are finished to match the case materials of their respective watches. The balance wheel is prominently displayed below the running seconds register at the 8 o’clock location, and visible below the 12 o’clock marker is a “crémaillère” rack system, which consists of a linear gear that moves in a straight line to engage a separate circular gear. The two superimposed discs that form the power reserve indicator move in opposite directions, and they are connected by a spiral spring in the center that moves in a similar fashion to a balance spring. Additionally, the streamlined power reserve indicator lends itself to a slightly more open display, and just like the larger 45mm models, the hands and hour markers on the Big Bang MECA-10 42mm watches are finished with Super-LimiNova to help increase their low-light visibility.

Despite offering the same functionality as their larger siblings, the new Hublot Big Bang MECA-10 42mm watches are powered by a re-engineered movement that takes the fundamental design of the MECA-10 and distills it into a smaller and more refined expression of Hublot’s 10-day concept. Officially known as the Manufacture Caliber HUB1205, the new 29-jewel movement consists of 264 individual components, and it offers a manually wound design with an architecture formed by three linear bridges mounted to a highly open-worked circular mainplate. Additionally, the Hublot Cal. HUB1205 positions its balance wheel on the dial of the watch to help draw attention to Hublot’s patented fine adjusted mechanism, which appears at the 8 o’clock location as an intricately shaped component that incorporates the brand’s H-shaped logo into its structure.

Running at a frequency of 21,600vph (3 Hz), the Hublot Caliber HUB1205 actually has the ability to run for longer than the 10 days of autonomy listed on its official spec sheet. With that in mind, its power reserve indicator only goes up to 10 days (approximately 240 hours) because this represents the optimal range for chronometric performance. The satin-finished and hand-angled bridges are galvanically treated either rose gold, metallic gray, or black to match the colorways of the three Big Bang MECA-10 42mm models, and the new Caliber HUB1205 movement also includes a silicon escapement that is entirely antimagnetic and non-reliant on lubricants. Aside from its technical upgrades, the revised architecture and updated finishing on the Caliber HUB1205 provide the movement with a more luxurious overall appearance compared to the micro-blasted surfaces that characterize Hublot’s larger 45mm MECA-10 models.

The titanium and King Gold versions of the Hublot Big Bang MECA-10 42mm are both paired with black line-textured rubber straps, which are completed by deployant-style clasps that match their respective cases. The titanium model receives a standard titanium clasp, while the clasp for the King Gold version is crafted from 18k King Gold and black-plated titanium; however, both clasps adhere to the same design that can be found on other Hublot rubber straps. Meanwhile, the Frost Carbon model is paired with a black Velcro strap to further lean into the lightweight construction of its case, and the strap’s fastening loop is crafted from black ceramic to further complement the watch’s dark monochromatic exterior. Additionally, just like the original 45mm MECA-10 models, the straps for the new 42mm versions connect to their cases using Hublot’s One Click system to facilitate tool-free strap changes.

When it comes to pricing for the new Hublot Big Bang MECA-10 42mm watches, the standard titanium model (ref. 444.NX.1170.RX) is naturally the most affordable among the trio with an official retail price of $23,000 USD. From there, the Frosted Carbon version (ref. 444.QN.1170.NR) is the next most expensive at $27,400 USD, and just as you would expect, the King Gold execution (ref. 444.OX.1180.RX) represents the top-of-the-line offering with a significantly higher price tag of $42,700 USD. Additionally, unlike many Hublot novelties that initially get introduced as limited editions, the new trio of 42mm Big Bang MECA-10 watches will be joining the catalog as standard-production models, and given how the original 45mm series expanded over the years to include additional case materials like Magic Gold and colored ceramic, I can only imagine that we will eventually see other iterations of the 42mm MECA-10 at some point in the future. For more information on the Hublot Big Bang MECA-10 42mm collection, please visit the brand’s website.