multiple commands in linux shell

I have just come across an article describing process of installing containerD runtime and I'm a little dubious about the command mentioned, maybe a typo but I want to get clarity on it. The command is as follows curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.lis Now as far as I know the apt-key add - is used to add the key and the contents are read from the piped standard output for which - is there but what about the echo after it, if this is a separate command shouldn't it be separated by || or a semicolon ;? I know the command is fetching key from the repo and then updating the apt sources list but I'm confused about the syntax of the command.