Keeping a single record for groups in sql table

I have a table for the "Features and benefits" of a list of products. In this table there is an item number, base part number, and three benefit columns. I want to change this to a dynamic table in which they can have any number of benefits, which I can do easily. The problem is the features and benefits do not change between items under the same base part number. For example under the base part "708" the items 708/s, 708/m and 708/l would all have the same features and benefits, so I want to get rid of the redundancy by removing the item column and just开发者_如何学Python have a single entry for each distinct base part number. How would I go about this?

You might need to introduce a 'benefits grouper' field in your table, and relate that to another table with benefitsGrouperID, benefitSequence, and benefit