Ready-Block EDM blanks are designed for EDM applications. The ready-to-use blanks are pre-hardened, squared and ground, eliminating the need for customers to machine and heat treat them prior to use. They are available in many popular tool-steel grades. Each block is first precision machined to a specific thickness, width and length, within +.010/.020-inch tolerance. They are then hardened and tempered to a standard hardness. A starter hole is included at the customer’s request.