Limit number of chars in a field

[Bojsza]

I can't the field property that I can select for limiting the number of 
characters a user may enter into a field. I have fields that I want to 
allow up to but not exceeding 11 characters.

I have opened other example scripts but they all allow more characters 
than what the field can show?

Any suggestions?

Thanks for all the support...

regards,

Glen