Most aftermarket copper infused seats will require a special cutting insert.  Our Cermet or PCD inserts are recommended for these applications. Cermet does not come coated, and will look very similar to a non coated carbide insert.  Cermet is harder than carbide, and will stay sharp longer.  We only offer 3 sided inserts in Cermet in one grade.  Contact our tech department if you need a customer Cermet insert.