This category parameter is used for proper navigation and its addition is intended. Could you please let me know why this part should not be there?
It will not cause the duplicated content problem, because canonical tag of the link
Code:
http://www.meditools.com.au/shop/sheep-tail-docking-banding-elastrator.html?category_id=97
will point it to
Code:
http://www.meditools.com.au/shop/sheep-tail-docking-banding-elastrator.html
Please, let me know.
Thank you.
Tony