You can add up to 4 Purezone devices in the Purezone app.

• Note:  Purezone devices that have been shared by others with your Purezone account email address through spa sharing do not count against the number 
• You can add an unlimited number of shared Purezone devices to your Purezone account 
• If you attempt to add a fifth device, you will be prompted to enter a Commercial key.  You can email Purezone support to request the Commercial key