The cold brew avenue, cold brew system kettles have a diameter of:
5G System = 11" Diameter
15G System = 15.8" Diameter
30G System = 19.7" Diameter
50G System = 23.6" Diameter
The valve setup will stock off the front of the system another few inches.  If you select the standard valve setup, that will extend off the front of the kettle roughly 3.5".
If you select the Deluxe Triclamp valve setup, that will extend off the front of the kettle roughly 7".