POWERTEC High Speed Steel (HSS) Knives are made of premium High Speed Steel (HSS) with performance that meets or exceeds OEM product. The manufacturing process started with premium HSS material, followed by strictly professional machining and quality control that ensure extreme sharpness, precision, balancing, and tight tolerance in every piece of "POWERTEC HSS Knife" product. The final Heat Treatment enhances the hardness and durability. "POWERTEC High Speed Steel (HSS) Knives" stay sharp and last longer than conventional product. We guarantee that "POWERTEC High Speed Steel (HSS) Knives" meet or exceed OEM quality and industrial standard. Plastic case packaging. 《Compatibility》Planer Blades for Delta TP305, TP400LS, 22-560, 22-565 Planer, Replacement Planer Knives for 22-562. Planer Blades Replacement Knives for Ryobi AP-12.