Product Model More Characters
商品型號字多啲
Warning: Please check the form carefully for errors!
Product Model must be greater than 1 and less than 64 characters!
警告： 資料未正確輸入！
商品型號必須在3至24個字之間！
Customer ask:
how can i remove this limit or extend to 80 character...
Why won't support file name length more than 63 char?

Solution is HERE after I installed this extension
I have never heard of this issue. I tried creating the model with 128 characters in it and it worked.

This extension will solve your problem of the default limit 64 characters in Product Model (English)
While in Chinese is being limited to 24 characters only.