[DIABLO2099]

I'm in the process of making a new hat shop for UN which will have some brand new hats made by the GATs who work here. However, before (and still to this date), there was a problem with custom playerworld hats overwriting global ones and also overwriting other servers' hats. I believe hats must have at least 3 digits after the word 'hat' in the filename for it to actually work online. So this brings me to my question...I want to know what hat numbers are safe to use without overwriting globally made ones, if any at all. Thanks in advance for any help.