SonicProtect for TZ600 FAMILY (TZ600, TZ600P) for 3 Years Equivalent of AGSS.
This is a subscription, and the licence extends your current TZ600 or TZ600P appliance so you can later purchase one of the SonicWall TZ600 Family (Gen 7 TZ670 or next-gen equivalent - possibly called the TZ680?) via the Secure Upgrade (Appliance Only) with no Attached Subscription (Existing SonicWall Customers Only).
The TZ600 & TZ600P go End of Support on 16th April 2026, so you would need to upgrade the hardware before then.
More information: SonicProtect Subscription | SonicWall