Hi,
The code displaying that is not in a view file but in the file administrator/components/com_hikashop/helpers/cart.php in the function "displayButton".
Actually, that code will be moved to a view file which will be called "show_quantity" starting in next release of HikaShop. So you would have found it right away with next version, but for now, either you directly edit that helpers/cart file, or you use a quantity field display override in your template, as explained in the developer documentation:
www.hikashop.com/support/support/documen...tation.html#override