size of a killer instinct arcade monitor

hi all

I have a question...

How large is an arcade monitor for the arcade cabinet killer instinct?  On the internet I find different sizes, the manual says 25 inch, another source says 26 inch and recently I heared the manual is wrong and midway arcade cabinets need an 28 inch...  I am very confused, does someone know which is the right size?

Thanks in advance

Roel

Factory they come with 26inch tubes, 25inch chassis.