A 1-license add-on to add a license onto a Sync'Em Pro version 1.xx License ID.

Add-ons are delivered via a licensing code called an Add-On ID.

Each of the add-on licenses within a Sync'Em Pro 1.xx Add-On ID can be used to increase, by one, the number of licenses in a Sync'Em Pro 1.xx License ID.

Note: although an Add-On ID contains licenses, those licenses can only be added onto an existing License ID — they can not be used to license an application, directly.