If you just rename it to "sizes", or anything else that isn't a reserved word, then it will fix your issue.
You should be careful using reserved words. I see you also have a column in your database named "range", which is a reserved word in MySQL. It could come back to haunt you. Anytime you name something like a form element, database column, or database table, using a function name that exists in the language that will refer to it, you can run into difficulty.
MySQL reserved words can be found here:
It can be difficult to keep track of all of the reserved words, so I usually don't use actual words for form elements or column names. I use compound words, which will never be reserved like : "ProductSize" and "DataRange". If you always use two words, you never have to worry they might be reserved. You can also separate them with underscores.