MB&F Turns HM4 Thunderbolt Prototype Into Piece Unique

MB&F Turns HM4 Thunderbolt Prototype Into Piece Unique

Adrienne Faurote
By Adrienne Faurote November 24, 2020

In 2010, MB&F launched the HM4 Thunderbolt. This aviation-inspired watch was even among the rest of the collection of the brand an eyecatcher. That same year it also won the prize for Best Concept & Design Watch at the Grand Prix d’Horlogerie de Genève (GPHG). Its construction, of both the case and the movement, was complex, even by MB&F standards. Only 100 were made, the last one being delivered to a collector years ago. To commemorate its 10th anniversary, MB&F took the original prototype of the HM4 Thunderbolt and made it into a piece unique.


To turn this watch into something truly exceptional, MB&F took, not surprisingly, its inspiration from aviation history. The Curtiss P-40, built between 1938 and 1944, was one of the most essential aircrafts of the allied in WWII, playing a vital part in winning the war. It carried many nicknames, among them Kittyhawk, which MB&F adopted for this particular piece. Some of the Curtiss P-40’s were painted with a shark mouth and eyes at the front of the plane, making them more fearsome, and in the end, iconic. 


Miniaturist painter Isabelle Villa was responsible for painting the HM4 Kittyhawk with great detail. To accommodate the painting, MB&F treated the side of the case by removing microns of titanium, following the illustrations’ shape. This way, the painting became flush with the case. To protect it, a final coat of transparent varnish seals off the paint. As a finishing touch, MB&F aged the time and power reserve dials. This gives the watch a vintage look, amplified by the matching calf-skin strap. Now the watch that was the first is also the last to fly out of the manufacture of MB&F, as a piece unique honoring one of the most iconic aircraft of WWII.