The Forney 72391 10-1/2-inch replacement cutter set for Forney 72390 are heat treated carbon steel cutters. Replacement cutters for Forney 72390. Forney Industries is one of America's longest operating family-owned metal working product companies. Founded in 1932, Forney offers more than 5,000 products for the hardware, automotive, farm and ranch and do-it-yourself markets. If you've got metal working questions, we've got answers. Were committed to your success regardless of location size or needs. Proof of purchase required. neglect, negligence or accident, or that has been used in any way contrary to the purpose intended.