The Rolex Cosmograph Daytona 126509 is the white gold Daytona with the black diamond dial. The current generation updated the case profile with slimmer lugs and a slightly reshaped bezel. The metal tachymeter bezel with the black enamel engravings is the standard Daytona layout. The diamond hour markers on the gloss black dial with the silver-ringed subdials set this apart from the standard baton-marker Daytonas. The Oyster bracelet with the polished center links matches the white gold case finish. VSF Watch Factory got the case geometry, the movement, and the diamond setting right.
| Spec | Detail |
|---|---|
| Factory | VSF Watch Factory |
| Reference | 126509 (Daytona 40mm, white gold finish, black diamond dial) |
| Movement | Dandong 4131 automatic chronograph, 1:1 clone, column-wheel, vertical clutch, 72-hour power reserve |
| Case dimensions | 40mm diameter, ~11.9mm thick |
| Material | 904L stainless steel, polished white gold finish |
| Bezel | Fixed stainless steel with engraved tachymeter scale and black enamel fill |
| Crystal | Sapphire with edge chamfering and AR coating |
| Dial | Glossy black with silver-ringed subdials and simulated diamond hour markers |
| Bracelet | 904L steel Oyster, polished center links, Oysterlock clasp with Easylink extension |
The movement. The Dandong 4131 is the current-generation Daytona movement. It replaced the 4130 in the 1265xx series. The 4131 uses a column-wheel and vertical clutch chronograph mechanism instead of the cam-actuated system found in cheaper chronograph clones. Start, stop, and reset are crisp. No stickiness. No wobble. The rotor runs on ball bearings and the bridges have the updated Côtes de Genève decoration. The power reserve is roughly 72 hours. The subdial layout has running seconds at 6, a 30-minute counter at 3, and a 12-hour counter at 9. All three subdials are fully functional. VSF's 4131 is a ground-up clone, not a modified 7750 with a decoration plate.
The dial. Glossy black with diamond hour markers. The diamonds are set in place of the standard baton indices. The subdials are silver-ringed with a fine concentric texture that catches light separately from the gloss black dial surface. The hands are the standard Daytona style with Chromalight fill. The diamond markers are the only deviation from the standard Daytona dial layout. Whether diamonds belong on a chronograph originally designed for race car drivers is a separate question. Rolex put them there. VSF matched the diamond setting and the subdial finish.
The bezel. Fixed steel with an engraved tachymeter scale filled with black enamel. The tachymeter measures speed over a known distance using the chronograph seconds hand. The engraved markings are clean and the enamel fill is even and permanent. The metal bezel is polished to match the case.
The case. 40mm in 904L steel polished to a white gold tone. The gen 126509 is solid 18K white gold. VSF uses a high-polish finish to replicate the cooler, brighter look. The current generation slimmed the lugs and reshaped the case slightly from the 1165xx series. The crown is a Triplock screw-down with crown guards. The chronograph pushers screw down and seal for water resistance. At 40mm and 11.9mm thick, the Daytona wears compact for a chronograph and fits under a dress cuff more easily than a Submariner.
The bracelet. Oyster with polished center links and brushed outer links. The Oysterlock clasp has a safety catch and a 5mm Easylink extension. The polished center links match the polished case and bezel. They will pick up surface marks with daily wear, which is true of the gen as well.