I have changed the cartridge on a tap and in the process have ruined the washer that sits between the very base of the tap and the sink, I am referring to the ring at the base in this image which is now split:
As a consequence water can now run below the tap and to the cupboard below. I don’t know what the name of the washer is below the tap, nor whether or not I’m likely to be able to source a replacement (I am aware that plumbers seem to suggest simply to replace the tap in situations such as this).
I don’t know the brand or model of the tap as it was installed in my house since new.
Best Answer
google
moen single handle faucet partsI found two terms
escutcheon gasketanddeck gasket