Rolex Cosmograph Daytona Ref. 116500 series – Rolex own Caliber 4130

In autumn of 1999 Rolex’s technicians were already nearly finished with their work, not only with the construction of the firm’s own caliber, but also with the years of testing that preceded its launch. The new Rolex Caliber 4130 debuted at the watch convention held in Basel, Switzerland in March of 2000. The Rolex Caliber 4030 Presents itself as a mature, uncommonly high-performance and unconditionally reliable chronograph movement.

This new Caliber construction results in a different Daytona model. The Hunter style construction (small seconds above the 6) rather than Léphine-style construction (with small seconds beside the 9). The result of this it’s a new dial appearance with different chronograph register’s position. The new Daytona dial also presents wide markers that makes it more readable.

With the Ref. 116500 Rolex includes the Stop-seconds function to the Cosmograph Daytona Chronograph that was not present in the old Cosmograph Daytona model.

Characteristics of the New Cosmograph Daytona watches – Rolex Caliber 4130:

Case: Oyster, screw-down push buttons; screw down triplock crown with flank protection; screw-down push-pieces; fully threated; screw-down back; sapphire crystal; water resistant to 100 meters. Diameter: 40 mm; height: 12.4 mm (slightly thinner than the Old Daytona model).

Dial: Less color contrast between dial and registers track, wide dial indexes and registers track edge in metal, Printing on dial: ROLEX OYSTER PERPETUAL, certification of official chronometer (COSC).

Movement: Automatic chronograph movement; Rolex Caliber 4130; 44 jewels, 28800 beats per hour; 72-hour Power Reserve, Rolex own’s spiral balance-spring; Kif shock absorption; bi-directional rotor; fine regulation with microstella screws, Breguet balance-spring, stop-seconds function, official chronometer with C.O.S.C. certification.

[Source: Rolex Daytona History and Reference Guide : eBay Guides]