Why is it that used machine advertiser's list two numbers for their cnc mills? Here is an example (X-Axis Travel: 21'' - 25'', Highest Spindle Speed (RPM): 5001 - 7500). I see this all the time but can not make sense of it. Either the X-Axis moves 25in or 21in.

Thanks
Brian

It may be that they get lazy and intend to show the table size and table travel, and combine them without thinking or assume you know what they mean.
Al.

I suspect it's because they didn't really measure it.