The standard ball head included with the package has a diameter of Φ17mm. If you wish to mount the device on a 1" (25.4mm) mounting bracket or arm, please purchase the 1" RAM Ball Head accessory and replace the standard ball head with it.
Ball Head Size: Φ17 mm Standard, 1″ RAM Option
CHIGEE Displays ship with a 17 mm ball head; a 1-inch RAM ball head accessory is available for RAM-style arms.