title: Prestashop concatenate id_product with size
body: <p>I need to know how I can concatenate ID of a product with its size from cart page using php.
  The idea is to be able to take the ID of a product with his size in this format: 1922-41, 1922 is the ID product and 41 is the size.
  I know that the variable $product has many attributes but I'm not clear how to get the size of a certain product from the cart page.
  Thanks in advance!</p>