Nickel base, XRF set of 18 discs (7 mm), see BS-263-7MM, BS-H1B-7MM, BS-H6A-7MM, BS-H2C-7MM, BS-H8-7MM, BS-H3B-7MM, BS-600-6-7MM, BS-625D-7MM, BS-690-7MM, BS-718A-7MM, BS-800-7MM, BS-825E-7MM, BS-925-7MM, BS-750A-7MM, BS-400D-7MM, BS-500D-7MM, BS-200A-7MM, BS-197A-7MM