PFERD Reamers & Countersinks Countersink 609865 - PFERD 25202121, The PFERD 25202121 Countersink is a high-speed steel machining tool designed to DIN 335 standards with a 40 mm diameter. It features a 90-degree angle ideal for creating precise countersink holes in various materials. Typically used in metalworking and woodworking applications, this single piece ensures efficient and accurate performance. PFERD 25202121 KES countersink HSS 40mm 90° drop for steel & metals