Qty. 10, Triumph, by Korloy. TPMR 221 NC320 Carbide Turning Boring Bar Inserts. TPMR 110304. Grade NC320 is a CVD coated grade, primarily for machining carbon, alloy, and tool steels, including cast steels. iso P20-P30 Made in Korea. Price is for one pack of 10 inserts. Multiple packs available. See my store for more inserts and other cutting tools. Make me an offer on multiple items. Shipped USPS first class package