Angelus reaches new chronometry achievement with U51 Diver Tourbillon

Luxferity, 29.01.2020


Angelus keeps with its tradition of utilizing technologically forward materials to manufacture highly complicated and aesthetically interesting timepieces. The House stretches the limit of its famous diving tourbillon movement, adding power reserve of more than 100 hours to its list of features.

While meeting the required diver’s watch criteria, the U51 Diver Tourbillon comes with high technical features. In fact, the A-310 calibre is dedicated to efficiency, with a silicon lever escapement and with all bridges as plates made of titanium. Furthermore, Angelus’ engineers and watchmakers pushed the boundaries with a more than 100 hours power reserve while keeping the 28,800 vibrations per hour (4 Hz) frequency, ensuring a high precision. Finally, the tourbillon cage is set on a ball bearing instead of pivots to gain in stability.

Even though the U51 Diver Tourbillon is intended as a high-performance sporty timepiece, the skeletonised movement has been carefully decorated with sandblasted finishing, enhancing the natural colour variations of the titanium.

The 45 mm titanium case features two large screw-down crowns. The two-position crown at 4 o’clock is used for winding and setting the time, while the crown at 2 o’clock is used to rotate the unidirectional 60-minute rotating bezel. Opposite, at the 9 o’clock position, a helium escape valve is placed to ensure the watch’s water resistance to 300 meters (1,000 feet), even during saturation diving so the helium molecules could not make their way into the case under pressure.

Careful attention has been given to the aesthetic of the U51 Diver Tourbillon. The case is masterfully manufactured with a subtle interplay between sandblasted, brushed and polished surfaces, which takes full advantage of the titanium’s unique colours properties. The bezel of the case as the chapter ring are carved, recalling waves. The open display appeals with a contrasting chapter ring of stormy blue and striking orange colours. The hands, indexes and Arabic numerals are all filled with Super-Luminova for optimal readability.

The U51 Diver Tourbillon comes on a matching blue rubber strap embossed with an Angelus logo and a titanium folding buckle.

U51 Diver Tourbillon

Technical specifications


Hours, minutes, small seconds, unidirectional rotatable 60-minute indicator


Calibre - A-310, mechanical hand-wound, one-minute flying tourbillon

Jewels - 23

Diameter - 32.80 mm

Height - 4.30 mm

Power reserve - ~120 hours

Frequency - 4 Hz / 28,800 vph

Lever escapement - Silicon

Decoration - Sandblasted plates and bridges, wheels with Angelus six-spoke design, tourbillon cage with chamfered and polished edges


Openwork with blue and orange chapter ring. Hours’ indexes, chapter ring’s Arabic numbers and hands filled with Super-Luminova


Material - Grade 5 titanium, sandblasted, brushed or polished finishing

Diameter - 45.00 mm

Thickness - 12.47 mm

Crowns - Screwed and engraved with Angelus logo

Crystal - Box shaped sapphire with anti-reflection coating both sides

Back - Sapphire

Water resistance - 300 m / 1,000 ft


Material - Blue rubber embossed with Angelus logo

Buckle - Folding, grade 5 titanium

Limited edition - 25 pieces



World retail price:

CHF 32’800 without taxes (prices can be subject to change)