In short: the Cartier Santos marks differently from a round watch. Its square case offers large flat surfaces, where the slightest scratch catches the light, and its bezel carries eight visible screws that stand slightly proud. On metal-bracelet models, the screwed links and the clasp mark fastest. The right kit depends above all on the size: Large, Medium or Small.
Why a Santos scratches differently
1. The flat surfaces of the square case
On a round watch, light glides over curves. On the Santos, the bezel and case form wide planes: a micro-scratch is visible from almost every angle.
2. The eight bezel screws
The Santos bezel is decorated with eight visible screws, a legacy of the model designed in 1904 for the aviator Alberto Santos-Dumont. Their heads stand slightly proud of the bezel and take the rubbing first.
3. The screwed bracelet and the clasp
The metal bracelet also features visible screws on its links. On the current Santos de Cartier, the SmartLink system lets you add or remove links without tools, and the QuickSwitch system lets you swap from the metal bracelet to a leather strap in seconds.
4. Changing the strap
QuickSwitch is practical, but each strap change is a moment when the watch is handled and set down: that is often when the case flanks pick up a mark. Do it on a soft cloth.
Model by model
Santos de Cartier Large
The large size, about 39.8 × 47.5 mm, and our best-selling Santos kit. Its large flat surfaces are the most exposed. See the Large kit
Santos de Cartier Medium
The medium size, about 35.1 × 41.9 mm. The same exposed areas as the Large, on a smaller scale: the kit is cut specifically for this size. See the Medium kit
Santos Small
The smallest size in our Santos range, with its own kit. See the Small kit
Santos Dual Time
A Santos with a second time zone, with its own kit. See the Dual Time kit
Santos-Dumont
The Santos-Dumont is the thinnest and dressiest version, usually worn on a leather strap. On this model, the case therefore carries all the protection: screwed bezel, flat surfaces and lugs. See the Santos-Dumont kit
Large or Medium: how to tell?
The easiest way is the warranty card. Without papers, measure the width of the case, without the crown: around 40 mm, it is a Large; around 35 mm, a Medium. If in doubt, send us a photo.
Protecting a Santos without polishing it
On a Santos, polishing is delicate: you have to work around the screws and preserve the crisp edges of the square case. A PreserveLayer™ film cut for your size freezes the current condition of the case, bezel and crystal, and of the bracelet with the Premium kit.
Frequently asked questions about the Santos
Does the film cover the bezel screws?
The kit is cut to the shape of your Santos, taking its screwed bezel into account. If you have a specific question about an area, write to us with a photo of your watch.
My Santos is on a leather strap: which kit should I choose?
If you only wear it on leather, the Essential kit, which protects the case, is enough. If you switch to the metal bracelet with QuickSwitch, the Premium kit also protects the bracelet.
Why do scratches show so much on a Santos?
Because its square case offers wide flat surfaces that reflect light evenly: a micro-scratch breaks the reflection.
Not sure of your reference? Here is where to find it.
By the ChronoSkin team, French maker of protective films for watches. Updated 2 November 2026.