Stock Sync provides you, the user, an easy way for the mapping field which is the Guided Field Mapping.
How to use the Guided Field Mapping:
1. You upload a sample of your feed file to the space provided.
2. The Upload limit is 2.0mb only.
3. If you have a feed file that is way bigger than that, then I suggest you create a new file with only the header since you are trying to map the field.
4. After the upload is done, you should be able to get a dropdown list for all your field mappings.