Just to warn you - although you can put Yubikey 5C on a keychain, it's not robust, and the plastic disintegrates after light use in just months. I had two that got destroyed. Unlike the USB-A, which are highly resilient to wear, the USB-C version are greatly subpar! Given how expensive this is and how important is, it's highly disappointing that they didn't put more thought into the material selection process! Or maybe that was the main idea - make you buy a new key every year.