The Cartier Santos WSSA0009 is the reference that brought the Santos back. Introduced in 2018 as the large steel model of the relaunched collection, it set the template for every modern Santos that followed: the rounded square case, exposed bezel screws, silvered opaline dial, and the QuickSwitch system that made strap changes part of the ownership experience. It stayed in production for years before being succeeded by the WSSA0018, which is why so many WSSA0009s are on wrists today — and why finding the right replacement strap for this reference is one of the most common questions we get.
This guide covers the correct strap size for the WSSA0009 and the most popular Helvetus strap options for this model.
Cartier Santos WSSA0009 Strap Size and Fit
Correct sizing comes first. For the Cartier Santos WSSA0009:
- Model: Santos de Cartier, large model
- Case width: 39.8 mm
- Case shape: square
- Strap system: Cartier QuickSwitch (tool-free interchangeability)
This means the watch requires a 21mm (Large) strap made for the Santos quick-release system. When ordering, simply select the 21mm (Large) option on the product page.
A standard 21mm strap will not work here. The Santos case has no traditional lugs, so only straps built for the QuickSwitch system will click in securely and sit flush with the case. Every Helvetus Santos strap is designed exactly for this fit.
Why the WSSA0009 Was Made for Strap Changes
The Santos line goes back to 1904, when Louis Cartier created a watch for the aviator Alberto Santos-Dumont — one of the first wristwatches ever made for men. The 2018 relaunch kept that heritage intact but added something practical: QuickSwitch, which lets you swap between bracelet and strap in seconds, no tools needed.
Most WSSA0009 owners use this for two reasons. First, rotating straps protects the original steel bracelet from daily scratches, which matters on the pre-owned market. Second, a strap swap completely changes the character of the watch — the same case goes from boardroom to weekend in about ten seconds.
The Best Straps for the Cartier Santos WSSA0009
Helvetus offers rubber and leather straps made specifically for Santos quick-release models, including the WSSA0009. You can explore every compatible option here: Cartier Santos Quick Release Strap Collection.
Below are the most popular choices among owners of this reference, matched to the details of the watch itself.
Blue Rubber Strap
The WSSA0009 carries blued-steel sword hands and a faceted blue spinel in the crown. A blue rubber strap picks up exactly those details, which is why it has become one of the most popular strap choices for this model. It ties the whole watch together while keeping it sporty and comfortable for daily wear. Blue Rubber Strap for Cartier Santos Quick Release
If you want to lean into the Santos design language even further, the Navy Blue Rubber Strap with Screws echoes the exposed screws of the bezel on the strap itself.
Black Rubber Strap
Black rubber is the bestseller across the entire Santos range for a reason. Against the silvered opaline dial and steel case, black adds contrast and makes the dial appear even cleaner. It is the safest sporty option and particularly practical for travel, summer, and everyday wear. Black Rubber Strap for Cartier Santos Quick Release
Black Leather Strap
For a dressier direction, black leather is the classic pairing. It keeps the WSSA0009 elegant and understated, works with a suit as easily as with a t-shirt, and stays closest to how Cartier originally delivered the watch with its calfskin strap. Black Leather Strap for Cartier Santos Quick Release
Grey Rubber Strap
Grey creates a tonal, steel-on-steel look with the case and silver dial. It is more understated than blue or black, and owners who wear the watch mostly in professional settings tend to love this combination. Grey Rubber Strap for Cartier Santos Quick Release
Compatible With Other Santos References
All of these straps are built for the Santos quick-release system, so they also fit other modern Santos de Cartier references in the same size family. If you own more than one Santos, or upgrade later, the straps move with you. Browse the full range here: Cartier Santos Quick Release Strap Collection.
Final Thoughts
The WSSA0009 started the modern Santos era, and it remains one of the most wearable watches Cartier has ever made. A strap change is the easiest way to keep it feeling new — and to keep the original bracelet safe.
Helvetus is a leading name in aftermarket straps for luxury watches, trusted by more than 50,000 customers worldwide. Every Santos strap is engineered for an exact fit on the WSSA0009, rubber straps are covered by a lifetime warranty, and every order ships free worldwide with no import costs.
Find the perfect strap for your Santos WSSA0009 in the Cartier Santos Quick Release Strap Collection.
