Word or phrase similar to Unique Selling Proposition (USP) referring to the seller (manufacturer)
Focusing on the request for a word / phrase...
used to refer to the advantages the manufacturer (seller) has in making this product.
...I'd say the company should play to their strengths.
play to (one's) strengths
- To prioritize using one's natural abilities and specific skills, especially by pursuing tasks or goals suited to such skills.
After his disappointing Western-themed family drama, it's nice to see the director once again playing to her strengths with a film grounded in humor and wit. - To put one in a position that allows them to best use their natural abilities and specific skills.
We're going to have everyone try out the different positions on the field so we can find everyone a role that plays to their strengths.
Essentially that means the company should choose to make a product they're particularly good at making (specifically, something they're much better than their competitors at making).
I have heard the phrases “standout production” and *standout manufacture” in this context.