Design notes: Movement Cal. 3301
Design notes

Design notes: Movement Cal. 3301

Cal. 3301 Self Winding

- Based on Sellita SW300-1b
- 3 Hands (Hr, Min, Sec), Hacking function
- Top Grade 
- 56 Hr Power reserve
- 28’800 vibrations per hour (4 Hz)
- 25 Jewels
- Adjusted to 5 Positions
- Thickness: 3.6mm
- Incabloc shock absorber
- Côtes de Genêve on bridges, Snailing on undercuts, Perlage on base plate
- Heat-blued screws, 4N Rose gold finish, Skeletonized rotor & barrel, Polished bevels on bridges
- Manufacturer: Sellita Watch Co S.A., La Chaux-de-Fonds
- Manufactured: Switzerland

Cal. 3301 is a luxuriously finished movement created in collaboration with Swiss movement manufacturer Sellita. It is based on the Sellita SW300-1b, which is the equal design to the original ETA 2892-A2, an iconic caliber developed in the 1970s and adopted by almost all major Swiss watch brands since - Omega, Breiting, IWC, Cartier, Longine, Chopard, and even the legendary George Daniels for his Millennium Wristwatch with a modified Co-Axial version of the ETA 2892-A2.

The design of the ETA 2892-A2 is remarkable for its thinness of 3.6mm, which is still one of the thinnest automatic movements on the market. However, even with its exceptional thinness, the ETA 2892-A2 does not compromise on its robustness and durability, with superior shock absorption and winding rotor stability. The architecture of the ETA 2892-A2 has stood the test of time with 47 years on the market, making it one of the most battle-tested movement designs throughout history, and has proven that it is a superlative design with optimal composition and balance.

Sellita SW300-1b is a non-date three-hand movement with an improved 56hr power reserve, without sacrificing the smooth second hand sweep of a 4 Hz frequency. The thinness of 3.6mm is one of the primary reasons we chose this as the base movement for the Serenity, to offer an ideally thin 9.2mm case height, which provides the wearer a comfortable and sartorial wearing experience.

Cal. 3301 offers a heightened level of finishing with Côtes de Genêve on bridges, snailing on undercuts, perlage on base plate, heat-blued screws, polished bevels on bridges, 4N rose gold finish, and signature skeletonized winding rotor & mainspring barrel. These details add up to bring out the beauty of the movement architecture and to have a coherent design language with the rest of the watch.

You will be able to appreciate and enjoy this remarkable movement through an open display sapphire case back for many generations - with proper care and periodic servicing perhaps twice a decade.


Design notes: Case Design