Where Can I find the API Call (Field ID) for HS Code and Tax Code on the Item/Product?

Hi Support - Looking at doing an integration with Celigo from NetSuite to Shopify. We need to map 2 custom fields values from NetSuite to Shopify Fields on the Item Record. Field #1 HS Code and Field #2 Tax Code.

I am looking for the API Call/Field ID for both of these fields on the Item Record.

For example: The Compare at Price field API Call/Field ID is “compare_at_price”.

I have looked at several posts and may have found HS Code = harmonized_system_code. But need verification and also what Tax Code would be.

Any help would be appreciated! Thanks!