Weber 22.5" grate demensions?

Just a quick question here, what is the exact dimensions of a Weber 22.5" grate. Is the actual grate a 21.5" or 22.5"? I have a customer who would like me to custom cut a grate for this Weber grill but he and I are not certain of the actual grate size as it is for a gift for someone else. He doesn't actually have the grill in his possession to take a measurement. The only reason I ask is because I know a lot of people use the factory Weber grate for their UDS creations and most drums are 22.5" outside diameter. I have cut several grates for USD builds and the customers in those cases all want a 21.5" grate to fit the drum.

Thanks in advance

That answers that, Thanks CD!!!