1)Had a query regarding using these codes. Should we put UPC code on each bottle packing or only on outside of carton?
>>UPC code is unique product code which is provided by us. By using this code on Amazon seller central account you can list your product on Amazon.UPC is required for product listing and when you convert your stock to FBA that time amazon provide you a label that need to put on product carton.
>>You need one UPC for one product and it really doesn’t matter how many products you are selling with it. You don’t need to print UPC on each product, you need to put label on barcode label provided by amazon on product carton in which you sending stock to FBA. When you convert inventory to FBA and prepare shipping that time they provide you label.
>>In nutshell you Don’t have to put UPC code on each product, Its totally your choice either you want to or not. You have to use UPC at the time of listing on amazon.
2) That means if i have 100 bottle with UPC code XYZ so should I put XYZ on each bottle packing ?
>>No it is not mandatory to put UPC code xyz on each product packing.
3) Also If I am ordering bottles of 1000 ML and 600 ML, should i use different UPC codes for both variety ?
>>It is better to use different UPC code for 1000 ml and 600 ml with separate listing of both product listing.