'The purchase of a licence is a one-off payment, there are no annual renewal/update fees.
It is a perpetual license, you will be entitled to any version upgrades and additional device compatibility.
At a future date, should you need to, you can detach camera licenses from your current Synology box and apply them to a different box.
Please do not lose your actual code, neither we nor Synology can provide replacement for lost codes.'

Synology 4 Camera License Pack is used to add extra IP cameras to your Synology Surveillance Station. By default one camera license is installed. By applying this license key on the Surveillance Station you will be able to set up and manage an additional four network cameras.

'The purchase of a license is a one-off payment, there are no annual renewal/update fees.
It is a perpetual license, you will be entitled to any version upgrades and additional device compatibility.
At a future date, should you need to, you can detach camera licenses from your current Synology box and apply them to a different box.
Please do not lose your actual code, neither we nor Synology can provide replacement for lost codes.'

How do I install a license pack?