To replace the button on top of the handle or to replace a cartridge, you will need to remove the existing button with metal ring on top of the faucet handle.
Removing the existing button on top of the faucet handle and replacing it with a new button with metal ring is not obvious. You will need to use rubber gloves with a good grip to unscrew and remove the existing metal ring atop the handle. Then screw on the new button with metal ring. The video below demonstrates how to change the button.
Highly recommended tool: 17mm socket with long handle.
Highly recommended tool: 17mm socket with long handle.
Highly recommended tool: 17mm socket with long handle.