The model number is normally found inside the fridge or freezer. You will likely need to remove the salad drawer or freezer drawer to find the model number plate. Otherwise the model number is likely to be on the side or rear of the appliance.
Beko Fridge & Freezer Bottle Shelf Rack Tray for CFG1582S
BEKO Fridge Freezer Bottle Shelf Rack Tray 422 x 85 x 115 mm 5928630100
Beko Fridge & Freezer Door Shelf Rack Tray Genuine