You need the model and the 11 digit Product number (PNC) - or 12 digit service number - which is displayed on a sticker or data plate, usually on an internal wall within the fridge or behind the vegetable drawer.
Here's What you should See
Your model number may be a combination of letters and numbers. The Product number (PNC) will be 9 digits followed by a (/) or "space" and ending with 2 numbers. The service number will consist of 12 digits starting with the numbers "85".