Multiple choices for one size.
Ø210mm model: AR-210-T AR-210-J ARs-210 RC-210-J
Ø255mm model: HR-255-T HR-255-J HRs-255 RC-255-J AD-261iB
https://www.tjr-world.com/images/pdf/210-250mm-rotary-table.pdf

The most popular 4th axis rotary table table size is Ø210mm and Ø255mm which is TJR best seller. The Ø210-255mm 4th axis has been widely used in different industries shch as aerospace, automotive, IT, medical, and general engineering. TJR devotes all the resources to building the robust and stable Ø210 & 255 models by different transmission mechanisms. Ø210-255mm rotary tables can be driven by Worm & Worm Gear, driven by Roller Gear Cam, or driven by Torque Motor to fit various user needs. Within a decade, more than 12,000 units Ø210-255mm TJR rotary tables were sold globally. Simply the best solution to the 4th axis machining.