Described by the brand as the “climactic conclusion” of the line of ultra-light watches made for the tennis champion, the RM 27-05 Flying Tourbillon Rafael Nadal weighs just 11.5 g without its strap – or about two sheets of A4 printer paper.

Like many of Richard Mille’s watches, the RM 27-05 is cased in carbon composite, specifically Carbon TPT B.4. More compact than the brand’s typical watches, the tonneau-shaped case is a compact 37.25mm by 7.2 mm. And according to Richard Mille, it is shock resistant to about 14,000 g.

Initial thoughts

Richard Mille was the first to make ultra-light a thing in watches with the RM009 ALUSiC that was introduced almost 20 years ago. The brand took the concept to the extreme with the RM 27 that debuted in 2010. Weighing just 13 g without the strap, it was conceived for Rafael Nadal to wear while playing tennis.

The watches have gotten even lighter since then, and the RM 27-05 is the final chapter in the series. Weighing essentially nothing at 11.5 g without the strap, it is as lightweight as it gets for a mechanical watch of this type.

Besides being the most extreme example of Richard Mille’s ultra-light philosophy, the RM 27-05 is also quintessential Richard Mille in terms of style. The notched outline and vents on the case, and the hyper-mechanical appearance of the skeleton movement, are very much typical of the brand’s current design ethos.

In short the watch is very much Richard Mille. That also holds true for the price, which is over US$1 million as is now the norm for the brand’s most exotic watches. More than any other brand, the price has no relation to any of the intrinsic features of the watch, but it reflects Richard Mille’s status as the brand this particular segment of watches.

Though the RM 27-05 is technically impressive to a degree, it isn’t as exciting or revolutionary as the RM009 was in 2005 simply because 19 years have passed. That is perhaps reflected in the RM 27-05 being the last of the series. After all, Richard Mille himself has always had a keen understanding of his client’s tastes.

Monobloc design

Various tweaks were made to the internal and external construction of the RM 27-05 to minimise its weight. Amongst them is the one-piece case. Richard Mille cases are typically made up of three parts, with a case middle, bezel, and back.

However, the RM 27-05 has a one-piece case that accommodates the movement. In fact, the movement slots directly into the case and is secured without screws but instead held in place by a flange and bezel that’s held with screws against the case middle.

Another detail that sets the RM 27-05 apart is the use of Carbon TPT B.4. Developed over five years by North Thin Ply Technology (NTPT), the Swiss firm that’s Richard Mille’s longtime composite supplier, Carbon TPT B.4 can be milled even thinner than past composites according to Richard Mille.

This is achieved without sacrificing robustness or strength due to the composition of Carbon TPT B.4. Richard Mille says the material is “4% denser, the fibre 15% stiffer and the resin 30% stronger” than equivalent carbon composites used in its earlier watches.

Like the brand’s other ultra-light watches, the RM 27-05 has a crystal that’s plastic rather than conventional sapphire, which is heavier. The crystal is a PMMA polymer with an anti-scratch coating.

The lightness of the case means some concessions had to be made, which in this case is water resistance. While the watch can withstand up to 14,000 g of acceleration, the case is only water resistant to 10 m.

Ultra-thin now made ultra-light

The RM 27-05 is equipped with RM27-05 movement that beats at 21,600 beats per hour (3 Hz) and has a power reserve of 55 hours. It has a flying tourbillon at five o’clock that is mounted on ball bearings, and a “flying” barrel at 11 o’clock with the mainspring visible through the open-worked barrel cover.

Interestingly, the RM27-05 is derived from the ultra-thin RMUP-01 found in the RM UP-01 Ferrari. Unlike the RMUP-01 that was essentially deconstructed to achieve record-setting thinness, the movement in the RM 27-05 is relatively conventional with two hands in the centre of the dial.

The movement is largely conventional on its materials as well, with its base plate and most bridges in black-coated titanium, which is also used for the screws of the movement and case. Only the V-shaped bridge visible on the dial is in Carbon TPT B.4.

Key facts and price

Richard Mille RM 27-05 Flying Tourbillon Rafael Nadal

Diameter: 37.25 mm
Height: 7.2 mm
Material: Carbon TPT B.4
Crystal: PMMA polymer with an anti-scratch coating
Water resistance: 10 m

Movement: RM27-05
Functions: Hours, minutes, seconds, and flying tourbillon.
Winding: Manual-wind
Frequency: 21,600 beats per hour (3 Hz)
Power reserve: 55 hours

Strap: Black textile strap

Limited edition: 80 pieces
Availability: At Richard Mille boutiques starting May 2024
Price: About CHF1 million before taxes 

For more, visit richardmille.com