Product specification's value should can input value with textbox extention

Hi,i think Product specification's value should can input value with textbox extention. But now we choose the value(Attribute option)  from the dropdownlist control only when add the specification(Select specification attribute:). For example, if the Product specification has many values(>100) then we should input the values before. So could you  add a textbox control after the dropdownlist control , if  I  input a value in the textbox then the program should passed the textbox's value to database.

thanks!